Cyberoam Web Application Firewall (WAF) Guideindex-of.es/Attacks/403 Forbidden Attack/Cyberoam...

Web Application Firewall Guide

Version 10 Version 7 Version 7 Version 7

Document Version 10.04.4.0028 - 08/10/2013

Document Version 10.04.5.0007 - 30/11/2013

Cyberoam Web Application Firewall Guide

2/49

Important Notice Cyberoam Technologies Pvt. Ltd. has supplied this Information believing it to be accurate and reliable at the time of printing, but is presented without warranty of any kind, expressed or implied. Users must take full responsibility for their application of any products. Cyberoam Technologies Pvt. Ltd. assumes no responsibility for any errors that may appear in this document. Cyberoam Technologies Pvt. Ltd. reserves the right, without notice to make changes in product design or specifications. Information is subject to change without notice.

USER’S LICENSE Use of this product and document is subject to acceptance of the terms and conditions of Cyberoam End User License Agreement (EULA) and Warranty Policy for Cyberoam UTM Appliances.

You will find the copy of the EULA at http://www.cyberoam.com/documents/EULA.html and the Warranty Policy for

Cyberoam UTM Appliances at http://kb.cyberoam.com.

RESTRICTED RIGHTS Copyright 1999 - 2013 Cyberoam Technologies Pvt. Ltd. All rights reserved. Cyberoam, Cyberoam logo are trademark of Cyberoam Technologies Pvt. Ltd.

Corporate Headquarters Cyberoam Technologies Pvt. Ltd. 901, Silicon Tower, Off. C.G. Road, Ahmedabad – 380006, INDIA Phone: +91-79-66065606 Fax: +91-79-26407640

Web site: www.cyberoam.com

http://www.cyberoam.com/documents/EULA.html

http://kb.cyberoam.com/default.asp?id=487&SID=&Lang=1.

http://www.cyberoam.com/


3/49

Contents

Introduction .................................................................................................................... 7

Terminologies Used ................................................................................................................... 8

Defacement ............................................................................................................................. 8 Buffer Overflow ........................................................................................................................ 8 URL Parameter Tampering ..................................................................................................... 8 Cookie Tampering/poisoning ................................................................................................... 8 SQL Injection ........................................................................................................................... 8 Cross Site Scripting ................................................................................................................. 8 Cross-Site Request Forgery .................................................................................................... 9 Session tampering/hijacking/riding .......................................................................................... 9 Forceful browsing .................................................................................................................... 9

Need of WAF ............................................................................................................................. 10

Cyberoamm WAF ...................................................................................................................... 12

Core Concepts and Technologies ......................................................................................... 13 How Cyberoam WAF works .................................................................................................. 14

Deployment Modes ................................................................................................................... 18

1. Server Hosted on Public IP Address ........................................................................... 18 2. Server Hosted on Private IP Address .......................................................................... 19

Configure WAF .......................................................................................................................... 20

Web Servers .......................................................................................................................... 20 Exception ............................................................................................................................... 33 Global Settings ...................................................................................................................... 41 Alerts...................................................................................................................................... 43


4/49

Preface

Welcome to Cyberoam‘s – Web Application Firewall Guide.

Cyberoam Unified Threat Management appliances offer identity-based comprehensive security to organizations against blended threats - worms, viruses, malware, data loss, identity theft; threats over applications viz. Instant Messengers; threats over secure protocols viz. HTTPS; and more. They also offer wireless security (WLAN) and 3G wireless broadband and analog modem support can be used as either Active or Backup WAN connection for business continuity.

Cyberoam integrates features like stateful inspection firewall, VPN, Gateway Anti-Virus and Anti- Spyware, Gateway Anti-Spam, Intrusion Prevention System, Content & Application Filtering, Web Application Filtering, Data Leakage Prevention, IM Management and Control, Layer 7 visibility, Bandwidth Management, Multiple Link Management, Comprehensive Reporting over a single platform.

Cyberoam has enhanced security by adding an 8th layer (User Identity) to the protocol stack. Advanced inspection provides L8 user-identity and L7 application detail in classifying traffic, enabling Administrators to apply access and bandwidth policies far beyond the controls that traditional UTMs support. It thus offers security to organizations across layer 2 - layer 8, without compromising productivity and connectivity.

Cyberoam UTM appliances accelerate unified security by enabling single-point control of all its security features through a Web 2.0-based GUI. An extensible architecture and an ‗IPv6 Ready‘ Gold logo provide Cyberoam the readiness to deliver on future security requirements.

Cyberoam provides increased LAN security by providing separate port for connecting to the publicly accessible servers like Web server, Mail server, FTP server etc. hosted in DMZ which are visible to the external world and still have firewall protection.

Note

Default Web Admin Console username is ‗admin‘ and password is ‗admin‘

Cyberoam recommends that you change the default password immediately after installation to avoid unauthorized access.


5/49

Typographic Conventions

Material in this manual is presented in text, screen displays, or command-line notation.

Item Convention Example

Server Machine where Cyberoam Software - Server component is installed

Client Machine where Cyberoam Software - Client component is installed

User The end user

Username Username uniquely identifies the user of the system

Part titles Bold and shaded font typefaces Report

Topic titles Shaded font typefaces

Introduction

Subtitles Bold & Black typefaces Notation conventions

Navigation link Bold typeface System Administration Appliance Access it means, to open the required page click on System then on Administration and finally click Appliance Access

Name of a particular parameter / field / command button text

Lowercase italic type

Enter policy name, replace policy name with the specific name of a policy Or Click Name to select where Name denotes command button text which is to be clicked

Cross references

Hyperlink in different color

Refer to Customizing User database Clicking on the link will open the particular topic

Notes & points to remember

Bold typeface between the black borders

Note

Prerequisites Bold typefaces between the black borders

Prerequisite Prerequisite details


6/49

Technical Support

You may direct all questions, comments, or requests concerning the software you purchased, your registration status, or similar issues to Customer care/service department at the following address:

Corporate Office

Cyberoam Technologies Pvt. Ltd.

901, Silicon Tower

Off C.G. Road

Ahmedabad 380006

Gujarat, India.

Phone: +91-79-66065606

Fax: +91-79-26407640


Cyberoam contact:

Technical support (Corporate Office): +91-79-66065777

Email: [email protected]


Visit www.cyberoam.com for the regional and latest contact information.


mailto:[email protected]




7/49

Introduction

Application Security is equivalent to preventing exception either in its security policy, or in the underlying system vulnerabilities in its design, development, or deployment. The rapid growth in technology has increased security threats concurrently. Automation lends sophistication to these threats against the Web applications, thereby addressing the need of security during the development. Developers write the Applications with an emphasis on time-to-market over security. Thus, with constant time to market pressure, a highly vulnerable Web infrastructure environment is created. Regardless of a carefully developed and audited application code, chances of vulnerabilities in the application and the framework that it supports still exist. Integrating various technologies to deploy complex architectures makes it susceptible to numerous vulnerabilities.

Such Applications are open to theft of intellectual property, resulting in business disruption, damage of brand reputation thereby loosing the customer trust. These vulnerabilities prove to be fatal for business directly affecting the revenue by endangering the sensitive data and critical business operations. In many cases, application security is also a legal requirement—such as complying with the PCI Data Security Standards, for example. Therefore, securing Web infrastructure of an organization requires attention, through knowledge and awareness from various areas of IT including the Web development, operations, infrastructure, and security teams.

Cyberoam‘s Web Application Firewall (WAF) aids in securing a Web application infrastructure. Cyberoam WAF is an operational security control, monitoring the HTTP and HTTPS traffic and protecting Web applications from attacks.

Note All the screen shots in the Cyberoam User Guides have been taken from NG series of appliances. The feature and functionalities however remains unchanged across all Cyberoam appliances.

Note

WAF is an additional subscription based module.

WAF feature is not available in CR15i, CR15wi, CR25ia, CR25wi, CR35ia, CR35wi CR15iNG and CR15wiNG Cyberoam Appliances.

HA failover and load balancing is not supported in WAF.

1

PA

RT


8/49

Terminologies Used

Defacement

Defacement, in Web site security terminology, describes a form of vandalism in which a Web site or Web page is altered or marred by an unauthorized individual or process. Generally, it is done by logging on administrator‘s account by means of SQL injections. The information on the Web site or Web page is often replaced with undesirable information. This damages the reputation of the organization, leaving Website‘s visitors with an impression that the Website may be insecure and hence turn them off in order to protect its own property.

Buffer Overflow

Buffer overflow is the condition that occurs when the data transferred to a buffer via a program exceeds the storage capacity of that buffer and overflows into adjacent or other buffers, corrupting the data already contained in them.

Unauthorized users overwrite data that control the program execution by launching a buffer overflow attack. They hijack and control the program to execute the malicious code instead of actual process code.

URL Parameter Tampering

Parameter Tampering is a type of Web-based attack in which certain query string parameter values of a Uniform Resource Locator (URL) sent to a Web site are altered in order to obtain unauthorized information. By doing so, unauthorized users can access the database and retrieve and/or modify its contents.

Cookie Tampering/poisoning

Cookie poisoning is modification of a cookie by an unauthorized person to gain access and control of the data within a cookie for malicious motives like theft of bank account details, etc.

SQL Injection

A SQL injection attack is insertion or ―injection‖ of a malicious code (SQL query) in to user input variables, which are coupled with SQL commands and executed. The attacker then forces database to execute the harmful SQL code that could potentially ruin database tables or to retrieve valuable information from database.

Cross Site Scripting

Cross-site scripting attacks are security vulnerability caused due to injection of malicious HTML tags or client side scripting code into HTML form fields of a Web page. On execution, this malicious script can access cookies, session tokens, or other sensitive information retained by the Web browser or may modify the information of the Web page.


9/49

Cross-Site Request Forgery

A Cross-Site Request Forgery (CSRF) attack is the one in which a request by malicious Website is sent to a Web application that a user is already authenticated against from a different Website. CSRF takes advantage of the trust that a Website lays in a user‘s browser.

Session tampering/hijacking/riding

Session hijacking is a method that takes over a TCP session, which is still in progress between two machines after obtaining or generating an authentication session ID and masquerading as the authorized user.

Forceful browsing

Forced browsing is XSRF attack in which user without a prior knowledge is forced to browse a content to gain access to resources, which are referenced yet are accessible. One of the methods implemented to enforce this attack is by manipulating the URL of the Web page and deleting sections from the end until an unprotected directory is found.


10/49

Need of WAF

Prior to touching the subject ―Need of WAF‖, it is vital to understand the basic difference between a firewall, IPS/IDS, and a WAF. Each of them is a crucial security device, ensuring the protection of organization‘s environment and sensitive data in diverse ways. A firewall generally, controls who can access what data at which time. An IPS/IDS detect packets and validates them on the bases of signatures that are often provided by vendors, blocking the invalid or malicious packets. A WAF, besides inspecting the packet will also verify the full request and response at the Application Layer.

User interaction to a Web Application includes HTTP/HTTPS methods, URL‘s, session IDs, cookies, etc. Intruders today, uses XSS, XRSF, SQL injection, session hijacking, buffer overflows to attack Web Applications hosted in private data centers or within the organization‘s local network. Several organizations depend on the network firewall and IPS/IDS to protect Web application threats. Is this solution adequate? The answer is ―No‖! Let us see why.

Firewall indeed safeguards the organization from network layer attacks but they permit application layer HTTP and HTTPS traffic to Web servers. Unauthorized users take advantage of this and implant attacks URL tampering, cross-site scripting, forceful browsing, SQL injection into Web traffic with the help of allowed application protocols, which effortlessly bypasses the network firewall. This is because, a traditional network firewall secures the third and fourth of the seven layers of the OSI model and fail to understand protocols and Web Application. Thus, a network firewall fails to control/filter sensitive data embedded in server responses, as it cannot validate user inputs to a Web Application and most of all do not have understanding about session data, limiting its effectiveness against Web application attacks.

IPS/IDS monitor the network traffic by matching the data within packets with data in a signature database. IPS takes an appropriate action if an anomaly is detected in the traffic and is suspected to be a threat. However, they fail to understand logic of Web application protocol and cannot differentiate between normal and malicious Web application request. Thus, it is possible, IPS allows an attack to pass without a detection or prevention if a signature for the attack does not exist within the signature database.

WAF deployment mitigates the risk of potentially vulnerable Web application. WAF unlike Firewall and IPS/IDS, keeps an eye on behavior of the Web request and response and provides protection at layer 7 – application layer of OSI model. They protect Web applications from the most common


11/49

and dangerous attacks by meticulously auditing the IP packets or protocols and analyzing the application logics. WAF verifies each request and response present in various Web service layers viz., HTTP, HTTPS. WAFs protect against OWASP Top 10 threats like cross-site scripting, session hijacking, SQL injection, parameter tampering, etc.


12/49

Cyberoamm WAF

Cyberoam Web Application Firewall (WAF) provides protection to applications in real time, rather than fixing them in advance or hardening them. Cyberoam WAF sits between the Web Server and the Internet-facing firewall, accepting all the client connection requests. It then analyzes HTTP/HTTPS traffic between a client browser and Web server at layer 7 (a whole session, not packets) and validates the requests received before allowing them to be processed by the Web/application server through a separate connection. This protects applications from attacks aimed at exploiting vulnerabilities found in the applications.

Depending upon various criteria including patterns of known/unknown attacks, protocol standards and anomalous application traffic, the Cyberoam WAF has the capability to enforce security policies. Although the prime focus lays on Layer 7 – the application layer, however it is not exclusively on it. It provides shielding against other form of attacks as well, like cookie tampering, forceful browsing, hidden field tampering etc. These tools typically protect against the classes of "user-induced" vulnerability in configured applications or in custom-developed code that make Web applications open to attacks, such as cross-site scripting, directory traversal and forced URL browsing. A WAF shields, however does not "fix" the underlying vulnerability. WAF reporting can be used to optimize the level of security.

Diagram – Cyberoam Web Application Firewall (WAF)

Cyberoam WAF implements Positive security model, a comprehensive security method, providing an independent input validation envelope to an application. Positive security follows a methodology ―allow only what I know‖ ―moving away from ―blocked,‖ end of the spectrum. The Cyberoam Web Application Firewall enforces a positive security model through Intuitive Website Flow Detector to automatically identify and block all application layer attacks without relying on signature tables or pattern matching techniques. The Web Application Firewall considers defined Web application behavior as ―good‖. Any deviation is considered ―bad‖, or malicious, and is blocked accordingly. This provides security against ―zero day attacks‖ and eliminates the need to manually populate and update signature tables. The Intuitive Website Flow Detector automatically adapts to changes in the Website.


13/49

Core Concepts and Technologies

Intuitive Website Flow Detector

Cyberoam WAF utilizes Intuitive Website Flow Detector to implement a positive protection model, ensuring usage of the Website and its applications exactly as intended.

For example, consider HTML form with a text field intended to accept a maximum of 50 characters (<input type=‖text‖ maxlength=‖50‖…>). When the text field is sent back to the server in an HTTP POST or GET request and if it contains beyond 50 characters, it will be blocked by Cyberoam WAF for violating the intended guideline. Similar is true for hidden form fields, URL query strings, cookie values, and other common targets of application manipulation attacks.

Intuitive Website Flow Detector also manages access to Web resources. All the Requests for URI‘s, which is not a part of the Web site, are blocked. For example, the URI /admin/ will be blocked, if it is not declared (as an <a href= ―/admin/‖…> for example) in a Web page somewhere on the site. In other words, an existing resource on the Web server will be blocked, if it is not intended to be accessed over the Web. With this approach, since both known and unknown URI-based worms will never be a legitimate part of any Web site, Cyberoam WAF safeguards the applications from the so-called ―zero-day‖ attacks. This approach is diagonally different from signature recognition technique, which is limited to block the explicitly recognized attacks.


14/49

How Cyberoam WAF works

Cyberoam WAF is placed between the Web/application server and the Internet-facing firewall. All the client connection requests received are accepted. Each request is then validated as per intended guidelines. Only if the request is valid, the Web/application server using a separate connection processes it.

Schematic Diagram

As illustrated above, incoming traffic is limited by the Internet-facing network firewall to the standard HTTP/HTTPS. Cyberoam WAF accepts the received client connections request that pass through the network firewall. To ensure that request received from the client conform to the intended guidelines, the HTTP specification, and any user-defined policies, it is evaluated by Cyberoam WAF. Using a separate connection generally a non-standard TCP port, the valid request is forwarded on to the Web/application server. In case the request is invalid it is blocked and never processed by the Web/application server.

Cyberoam WAF uses a sophisticated technology ―Intuitive Website Flow Detector‖ that automatically identifies and enforces intended guidelines in real time. Any modification to Web site is recognized automatically since Intuitive Website Flow Detector works in real time, with no requirement for cumbersome, time-consuming ―training‖. This ability of Cyberoam WAF enormously


15/49

reduces installation, setup, and on-going administration time.

Intuitive Website Flow Detector begins examining the outgoing HTTP/HTTPS responses (typically HTML content, either static or dynamically-generated) to identify the intended guidelines after defining at least one ―entry point‖ URI in the application (―/‖ by default). HTTP/HTTPS requests from clients (typically Web browsers such as Internet Explorer or Netscape Navigator) subsequently are validated before being forwarded on to the Web server (for example, IIS or Apache).

Intuitive Website Flow Detector ensures each HTTP/HHTPS request follows 3 step validation process:

Step 1. HTTP Specification Validation.

Diagram - HTTP Specification Validation

User sends a request to access Web site (www.abcretaillogin.com). Cyberoam WAF receives and validates the request for the protocol compliance HTTP 1.0/1.1. If the received request is found valid, it is forwarded to the Web Server. Web Server will respond with requested content (www.abcretaillogin.com/index.htm) which contains resources list like (―myaccount.htm‖, Image\Imaege1.gif)


16/49

Step 2. Intuitive Web Flow detector.

Diagram – Intuitive Web Flow Detector

Once the request is found legitimate and is sent to the Web server, Cyberoam creates rules dynamically (for resources like ―myaccount.htm‖, Image\Imaege1.gif) depending on the response received from the Web server. Exceptions, if configured, are allowed by Cyberoam and user can access them directly without being interrupted by Intuitive Guide Lines. Only legitimate request is forwarded to the Web server. A request if found to be a non RFC compliant protocol traffic or violating intended usage guidelines,, Cyberoam drops it, creating a rule dynamically for it. An alert notification in the form of email or a network ―pop-up‖ message, and/or HTTP is sent as per the user preference.


17/49

Step 3. User Define policies.

Diagram – User Defined Policies

If the user request (www.abcretaillogin.com/probe.htm) is received for which a dynamic rule do not exist in intended usage guidelines, Cyberoam WAF blocks the same and sends an error message (403 forbidden).

In order to allow the request that do not exist within the intended usage guidelines, an exception must be created by defining the user policies to override intended usage guidelines.


18/49

Deployment Modes

Cyberoam deployment is usually done within a data center of an organization, which also comprises of other zones viz., LAN zone, DMZ zone, etc. Server farm consisting of several Web servers, are hosted within the DMZ zone. The Administrator needs to publish the Web servers via Cyberoam WAF. One of the following two methods can achieve this:

1. Server hosted on Public IP Address 2. Server hosted on Private IP Address

1. Server Hosted on Public IP Address

Web server might have a public IP directly assigned to actual physical server without any NAT.

A user sends a HTTP/HTTPS request to access a Web server (here the request is to access Web server 61.10.15.18).

Cyberoam WAF receives the request. It validates the request depending on the level of scanning methodology.

If the received request is valid, the request is sent to the respective Web server.

However, if the request fails the validation and is found to be malicious, it will be dropped and thus not sent to Web server.

Alert notifications are sent (depending on user preferences) in the form of email, network ―pop-up‖ message, and/or HTTP.


19/49

2. Server Hosted on Private IP Address

In this deployment scenario, a Web server 10.10.10.2 is published via a public IP Address 61.10.15.18 using Cyberoam WAF.

A user sends a HTTP/HTTPS request for a public IP Address (here the request is sent for IP Address 61.10.15.18) to access a Web server that is hosted on private IP Address (Here private IP Address of Web server is 10.10.10.2).

Cyberoam WAF receives the request. It validates the request depending on the level of scanning methodology.

If the received request is valid, the request is sent to the respective Web server (Using Network Address Translation).

However, if the request fails the validation and is found to be malicious, it will be dropped and thus not sent to Web server.

Alert notifications are sent (depending on user preferences) in the form of email, network ―pop-up‖ message, and/or HTTP.


20/49

Configure WAF

Web Servers

Global Settings

Alerts

Web Servers

Use WAF Web Servers to view to Web Server and Exception details.

Web Server

Exceptions

Web Server

Web Server provides interface to add servers that are to be safe-gaurded by WAF. Web Server page displays list of servers and provides a way to manage them. You can:

Add

View

Search

Edit – Click the Edit icon in the Manage column against the Web Server to be modified. Edit Web Server rule window is displayed which has the same parameters as the Add Web Server rule window.

Delete – Click the Delete icon in the Manage column against a Web Server rule to be deleted. A dialog box is displayed asking you to confirm the deletion. Click OK to delete the

rule. To delete multiple rules, select them and click the Delete button.

To configure Web Server, go to WAF Web Servers Web Server.

Screen – Web Server

Manage Web Servers

Screen Elements Description

Add button Add new Web Server.

Name Name to identify the Web Server.

Public IP/FQDN The Public IP Address or FQDN to which the Web Server is added.


21/49

Private IP The Private IP Address to which the Web Server is added.

Domains Domains protected by the Web Server.

Public Port Port number through which Web Server communicates.

Edit Icon Edit Web Server.

Delete Icon Delete Web Server.

Delete Button Delete Web Server.

Table – Web Server

Search Web Server

Use the search facility for searching Web Server having a specific string.

Name

Click the Search icon to search Web Server for specific name. It can be searched on the following criteria: is, is not, contains and does not contain. Click OK to get the search results and Clear button to clear the results.

Screen – Search

Search Criteria Search Result

is All the Web Server names that exactly match with the string specified in the criteria.

For example, if the search string is Test, only Web Servers with the name exactly matching ―Test‖ is displayed.

is not All the Web Server names that do not match with the string specified in the criteria.

For example, if the search string is Test, all Web Server‘s except with the name exactly matching ―Test‖ are displayed.

contains All the Web Server names that contain the string specified in the criteria.

For example, if the search string is Test, all the Web Server names containing the string ―Test‖ are displayed.

does not contain All the Web Server names that do not contain the string specified in the criteria.


22/49

For example, if the search string is Test, all the Web Server names not containing the string ―Test‖ are displayed.

Table – Search Name

Web Server Parameters

To add or edit Web Server, go to WAF Web Server. Click Add Button to add a new rule or Edit Icon to modify the details of the rule. Web Server Rule Parameters are given below.

Note On adding a Web Server, a default Exception and a Firewall Rule is created for the same.

Screen – Web Server Parameters


Web Server Name Specify name to identify the Web Server.

Zone Specify zone to which the Web Server rule applies.


23/49

Web Server Hosted On Select from the available options on which the Web Server is to be hosted.

Available Options:

Public IP/FQDN – If selected, choose from following:

1. IP Address – If selected, choose from available IP Host or add an IP Host.

2. FQDN Host – If selected, choose from available FQDN Host or add a FQDN Host.

Private IP – If selected, choose or add IP Host for each of the following available options:

1. Public IP Address. 2. Private IP Address.

Web Server Protocol Select Web Server Protocol from the following available options:

1. Only HTTP 2. Only HTTPS 3. HTTP & HTTPS

Advanced Settings

The WAF Advanced Settings allows you to customize Web Server configurations. In most cases, the advanced settings on this screen should remain at their default values.

Performance Tuning

Screen – Performance Tuning Parameters

Max Connections Provide the maximum number of client connections that can be served simultaneously.

Minimum number of connections: 50

Maximum number of connections: 9999

By default, the value of maximum number of client connections is 5000.

Max listen queue Listening queue shall be used once the threshold for maximum connections is reached.

Minimum number of connections: 10

Maximum number of connections: 999

By default, the value of maximum number of pending connections allowed in listening queue is 511.


24/49

Keep alive timeout Provide the time in seconds for a subsequent request to wait before closing a connection.

Minimum number of Seconds: 5

Maximum number of Seconds: 999

By default, value for Keep Alive timeout is 15 seconds.

Enable Form Validation

Click to enable HTML form elements validation.

By default, form validation is in enable mode.

If enabled, to combat SQL command injection and cross-site scripting attacks, specify the dangerous characters to be filtered transparently from user input for each of the HTML parameters.

Enable Cookie Validation

Click to enable HTTP and HTTPS name/value cookie validation.

By default, cookie validation is in enable mode.

If enabled, select/specify the validation parameters.

Override Global Settings

Screen – Override Global Settings

Click to override the global settings for the respective Web Server.

By default, the parameter ―Override Global Settings‖ is in disable mode.

If enabled, select/specify the Global Settings parameters.

Table – Web Server Parameters


25/49

Web Server Protocol

1. Only HTTP

Screen – Only HTTP


Web Serve HTTP Port Provide a HTTP Port number.

By default, the port number is 80.

Note

If the Web Server is hosted on a private IP Address/host then provide a public and a private HTTP Port numbers.

In this case by default, both the public port number and the private port number will be 80.

SSL Offloading Click to enable SSL Offloading.

By default, form validation is in disable mode.

Published HTTPS Port Provide a HTTPS Port number.


Note

If the Web Server is hosted on a private IP Address/host then provide a public and a private HTTPS Port numbers.



26/49

Allow HTTP Traffic Also

Click to enable allow HTTP traffic.

By default, form validation is in disable mode.

Certificate A digital certificate is a document that guarantees the identity of an entity.

Certificate will be used by the WAF for secured communication for any request received for the Web Server.

In case of SSL offloading, certificate will be exchanged between client and WAF.

Select a Certificate from the available list.

Certificate Authority A certificate signed by a Certificate Authority (CA) identifies the owner of a public key.

Select a Certificate Authority from the available list.

Allow SSLv2 Select ―Yes‖ to allow SSLv2 client connection.

By default, the value is ―No‖.

Allow Weak Ciphers Select ―Yes‖ to allow weak ciphers.


Domains to protect Choose domains to be protected from the following available option:

1. All domains hosted on selected Web Server Host.

2. Specific domains hosted on Web Server Host.

In this case, select a domain or add a domain.

By default, the option ―All domains hosted on selected Web Server Host‖ is selected.

Back to top

Table – Only HTTP


27/49

2. Only HTTPS

Screen – Only HTTPS


Web Server HTTPS Port

Provide a HTTPS Port number.

By default the port number is 443

Note














28/49





Back to top

Table – Only HTTPS

3. HTTP & HTTPS

Screen – HTTP & HTTPS


Web Server HTTP Port Provide a HTTP Port number.


Note

If the Web Server is hosted on a private IP Address/host then provide a public and a private HTTP Port numbers.


Web Server HTTPS Port

Provide a HTTPS Port number.

By default the port number is 443

Note


29/49

















Back to top

Table – HTTP & HTTPS


30/49

Enable Form Validation

Screen – Form Validation


Text Specify the characters that require to be filtered transparently.

By default, the value of this field is ―<‖, ―>‖, ―"‖, ―'‖, ―;‖, ―(‖, ―)‖.

Select one of the following actions in case the input is one of the specified characters:

Alert

Block

By default, an alert is generated.

Text-Area Specify the characters that require to be filtered transparently.



Alert

Block

By default, the alert is generated.

Password Specify the characters that require to be filtered transparently.



Alert

Block


31/49

By default, the alert is generated.

Form Clean-up Click to enable HTML form clean-up.

By default, form clean-up is in enable mode.

If enabled, specify the number of days and hours. HTML forms older than the specified duration shall be cleaned up/ purged.

Minimum number of days: 0

Maximum number of days: 365

Minimum number of Hours: 0

Maximum number of Hours: 23

By default, the duration is 15 Days and 0 hours.

Back to top

Table – Form Validation

Enable Cookie Validation

Screen – Cookie Validation


Enable Strict Cookie Validation

Click to enable blocking of the request that contains a tampered cookie, thereby avoiding it to be forwarded on to the Web Server.

When a request containing a tampered cookie is received and cookie validation is in disable mode, then the tampered cookie will be stripped - off from request and the request will be forwarded to Web Server.

By default, cookie validation is in disable mode.


32/49

Enable Transition Period

Click to allow cookie attributes and values that cannot be validated.

It will be effective from the time cookie validation is enabled.

By default, parameter transition period is in enable mode.






Enable Cookie Cleanup

Click to enable HTTP - HTTPS cookie cleanup.

By default, cookie cleanup is in enable mode.

If enabled, specify the number of days and hours. HTTP- HTTPS cookies older than the specified duration shall be cleaned up.






Back to top

Table – Cookie Validation


33/49

Exception

Exceptions are the parameters on which WAF configuration are not applicable. You can:

Add

View

Edit - Click the Edit icon in the Manage column against the Exception to be modified. Edit Exception pop-window window is displayed which has the same parameters as the Add Exception window.

Delete – Click the Delete icon in the Manage column against a Exception to be deleted. A dialog box is displayed asking you to confirm the deletion. Click OK to delete the rule. To

delete multiple Exception, select them and click the Delete button.

To configure an Exception, go to WAF Web Server Exception.

Screen – Exceptions

View the list of Exception


Add Button Add new Exception.

Exception Name Name of the Exception.

Exception Type Type of the Exception.

Web Server Web Server for which the exception is created.

URL/Directory/URI URL/Directory/URI path.

Edit Icon Edit exception.



Table – Exceptions

Search Exception

Use the search facility for searching Exception having a specific string.

Name

Click the Search icon to search Exception for specific name. It can be searched on the following criteria: is, is not, contains and does not contain. Click OK to get the search results and Clear button to clear the results.


34/49

Screen – Search

Search Criteria Search Result

is All the Exception names that exactly match with the string specified in the criteria.

For example, if the search string is Test, only Exception‘s with the name exactly matching ―Test‖ are displayed.

is not All the Exception names that do not match with the string specified in the criteria.

For example, if the search string is Test, all Exception‘s except with the name exactly matching ―Test‖ are displayed.

contains All the Exception names that contain the string specified in the criteria.

For example, if the search string is Test, all the Exception names containing the string ―Test‖ are displayed.

does not contain All the Exception names that do not contain the string specified in the criteria.

For example, if the search string is Test, all the Exception names not containing the string ―Test‖ are displayed.

Table – Search Exception Name


35/49

Add Exception Parameters

To add an Exception, go to WAF Web Server Exception and click Add.

Screen – Add Exceptions


Exception Name Provide name to exception.

Exception Type Select the type of the exception from the available options.

The available options are as follows:

1. Entry Point 2. Unprotected Directories 3. Filter Exception 4. Cookie Exception 5. Form Exception

Web Server Web Server for which the exception is created.

URL / Directory /URI URL / Directory / URI path

Edit Icon Edit exception



Table – Add Exceptions


36/49

Edit Exception Parameters

To add an Exception, go to WAF Web Server Exception and click the Edit icon in

the Manage column against the Exception to be modified.

Screen – Add Exceptions






Table – Add Exceptions

Exception Type

1. Entry Point

Screen – Entry Point


37/49


Web Server Select the Web Server for which the exception is to be created.

URL/Directory Provide a URL/Directory path.

URL/Directory Properties

Click one of the following options:

HTTPS – Select if entry point/directory is to be accessed via an encrypted connection.

Ignore Case – Select if the entry point /directory validation should not be case sensitive.

RegEx – Select if the URL/Directory is a regular expression.

Back to top

Table – Entry Point

2. Unprotected Directories

Screen – Unprotected Directories



URL/Directory Provide a URL/Directory path.

URL/Directory Properties

Click one of the following options:

HTTPS – Select if entry point/directory is to be accessed via an encrypted connection.

Ignore Case – Select if the entry point /directory validation should not be case sensitive.

RegEx – Select if the URL/Directory is a regular expression.

Back to top


38/49

Table – Unprotected Directories

3. Filter Exception

Screen – Filter Exception



URI Provide a URI path.

Form Name Specify the name of the form.

Field Name Specify the name of the field

Field Type Select the field type from the available options.

The following are the available options:

Any

Checkbox

Hidden

Radio Button

Select

Text

Text-Area

Characters Specify the characters for which the exception id to be created.

Back to top

Table – Filter Exception


39/49

4. Cookie Exception

Screen – Cookie Exception




Field Name Specify the name of the field.

Back to top

Table – Cookie Exception

5. Form Exception

Screen – Form Exception





40/49

Form Name Specify the name of the form.

Field Name Specify the name of the field.

Field Type Select the field type from the available options.

The following are the available options:

Any

Checkbox

Hidden

Radio Button

Select

Text

Text-Area

Characters Specify the characters for which the exception id to be created.

Back to top, Continue with Alerts

Table – Form Exception


41/49

Global Settings

Global Settings are configurations that are applied on all the Web Servers by default. To alter these configuration, modify the Advanced Settings of the Web Server.

To view Global Settings, go to WAF Global Settings Global Settings.

Screen – Global Settings

Global Settings Parameters


Global Settings

Hide Server Identity Click to avoid disclosing Web Server‘s identity thereby


42/49

preventing banner – grabbing.

By default, the server identity is hidden.

Enable Passive Mode Click to enable passive mode for the Web Server to operate in ―report-only‖ mode.

All the requests that are received will be forwarded on to the Web Server.

Disable the passive mode of Web Server to identify report and block malicious activities.

By default, the Web Server will not be in passive mode.

Enable JavaScript Processing

Click to enable to interpret client – side JavaScript to extract Intended Use Guidelines.

By default, JavaScript processing is in enable mode.

Enable Strict HTTPS Click to enable enforcing the access to HTTPS resources via an encrypted connection.

By default, strict HTTPS is in enable mode.

Send Client IP Header Click to send ―WAF-Client-IP‖ i.e. the client IP Address in a custom HTTP Header to the Web Server.

By default, client IP Header will be sent to Web Server.

Allow Incomplete URLs

Click to allow incomplete URL‘s.

For example, If intended URL is ―http://www.domain.com/test/‖, but the user enters ―http://www.domain.com/test‖ (no trailing slash) in their browser's address bar, both will be allowed.

By default, incomplete URL‘s will not be allowed.

Enable Case-sensitive URL validation

Click to enable validation of case sensitive URL.

By default, case sensitive URL validation is in enable mode.

Enable Transform Error 500

Click to enable ensuring HTTP error code 500 from the Web server gets transformed into a HTTP 202 Accepted response code.

By default, Transform Error 500 is in disabled mode.

Error URLs

400 Bad Request Click to enable and provide a fully qualified URL.

If an HTTP error code 400 Bad Request occurs then it will be redirected to the provided fully qualified URL.


43/49

403 Forbidden Click to enable and provide a fully qualified URL.

If an HTTP error code 403 Forbidden occurs then it will be redirected to the provided fully qualified URL

405 Method not allowed

Click to enable and provide a fully qualified URL.

If an HTTP error code 405 Method not allowed occurs then it will be redirected to the provided fully qualified URL

Allowed HTTP Methods

HTTP Methods Specify the allowed HTTP Methods.

By default, the allowed HTTP methods are POST, GET, and HEAD.

Back to top

Table – Global Settings

Alerts

Based on the WAF configuration, certain system-generated events trigger alerts. These alerts are reports of actions taken on the request received.

To view Alerts, go to WAF Alerts Alerts.

Parameters

Screen – Alerts


Date & Time Date and Time when the alert was generated.

Action Displays action taken on the received request.

Source IP/Name Displays Source IP Address or Name of the request.

Reason Displays reason of the action taken.

Web Server Name Displays name of the Web Server.

Status Code Displays response status code of HTTP/HTTPS protocol.


44/49

Add Exception Click Add Icon to add an exception.

Table – Alerts

Add Exception






Table – Add Exception

Search Web Server

Use the search facility for searching Web Server having specific traffic. The search string can be either an IP Address or a string.

Click the Search icon to search Web Server for specific string. It can be searched on the following criteria: is, is not, contains and does not contain. Click OK to get the search results and Clear button to clear the results.

Screen – Search Web Server Name

Search Criteria Search Results

is All the Web Server parameters that exactly match with the string specified in the criteria.

For example, if the search string is Test, only Web Servers with the name exactly matching ―Test‖ are displayed.

is not All the Web Server parameters that do not match with the string specified in the criteria.

For example, if the search string is Test, all Web Servers except with the name exactly matching ―Test‖ are displayed.

contains All the Web Server parameters that contain the string


45/49

specified in the criteria.

For example, if the search string is Test, all the Web Server names containing the string ―Test‖ are displayed.

does not contain All the Web Server parameters that do not contain the string specified in the criteria.

For example, if the search string is Test, all the Web Server names not containing the string ―Test‖ are displayed.

Table – Search Web Server Name

Search Action

Use the search facility by clicking the Search icon for searching action taken on the request received.

Screen – Action


Denied All the received requests that are denied matches with the criteria.

Would be denied All the received requests that would be denied when the Web Server is not in passive mode, matches with this criteria.

Table – Search Action


46/49

Search Date & Time

Use the search facility for searching Web Server created on specific date and time. Click the Search

icon to search Web Server for specific string. It can be searched on the following criteria: is, is not, contains and does not contain. Click OK to get the search results and Clear button to clear the results.

Screen – Date & Time


is All the Date & Time parameters that exactly match with the string specified in the criteria.

For example, if the search string is 10, only Date & Time with the exactly matching string ―10‖ is displayed.

is not All the Date & Time parameters that do not match with the string specified in the criteria.

For example, if the search string is 10, all Date & Time except with the name exactly matching ―10‖ are displayed.

contains All the Date & Time parameters that contain the string specified in the criteria.

For example, if the search string is 10, all the Date & Time containing the string ―10‖ are displayed.

does not contain All the Date & Time parameters that do not contain the string specified in the criteria.

For example, if the search string is 10, all the Date & Time not containing the string ―Test‖ are displayed.

Table – Search Date & Time


47/49

Search Source IP/Name

Use the search facility for searching source IP/ Name of the Web Server. Click the Search icon to search Source IP/ Name for specific string. It can be searched on the following criteria: is, is not, contains and does not contain. Click OK to get the search results and Clear button to clear the results.

Screen – Source IP/Name


is All the Source IP/ Name that exactly match with the string specified in the criteria.

For example, if the search string is 172.16.16.16, only Source IP/ Name with the exactly matching string is displayed.

is not All the Source IP/ Name that do not match with the string specified in the criteria.

For example, if the search string is 16, all Source IP/ Name except with the exactly matching ―16‖ are displayed.

contains All the Source IP/ Name that contain the string specified in the criteria.

For example, if the search string is 172, all the Source IP/ Name containing the string ―172‖ are displayed.

does not contain All the Source IP/ Name that do not contain the string specified in the criteria.

For example, if the search string is 16, all the Source IP/ Name not containing the string ―16‖ are displayed.

Table – Search Source IP/ Name


48/49

Search Reason

Use the search facility for searching reason of the Web Server. Click the Search icon to search web server for specific reason. It can be searched on the following criteria: is, is not, contains and does not contain. Click OK to get the search results and Clear button to clear the results.

Screen – Reason


is All the reasons that exactly match with the string specified in the criteria.

For example, if the search string is Test, only reasons with the exactly matching string are displayed.

is not All the reasons that do not match with the string specified in the criteria.

For example, if the search string is Test, all reasons except with the exactly matching ―Test‖ are displayed.

contains All the reasons that contain the string specified in the criteria.

For example, if the search string is Test, all the reasons containing the string ―Test‖ are displayed.

does not contain All the reasons that do not contain the string specified in the criteria.

For example, if the search string is Test, all the reasons not containing the string ―Test‖ are displayed.

Table – Search Reason


49/49

Search Status Code

Use the search facility for searching source IP/ Name of the Web Server. Click the Search icon to search Source IP/ Name for specific string. It can be searched on the following criteria: is, is not, contains and does not contain. Click OK to get the search results and Clear button to clear the results.

Screen – Status Code


is All the status code that exactly match with the string specified in the criteria.

For example, if the search string is 403, only status code with the exactly matching string is displayed.

is not All the status code that do not match with the string specified in the criteria.

For example, if the search string is 403, all status code except with the exactly matching ―403‖ are displayed.

contains All the status code that contain the string specified in the criteria.

For example, if the search string is 403, all the status code containing the string ―403‖ are displayed.

does not contain All the status code that do not contain the string specified in the criteria.

For example, if the search string is 403, all the status code not containing the string ―403‖ are displayed.

Table – Search Status Code

Cyberoam Web Application Firewall (WAF) Guideindex-of.es/Attacks/403 Forbidden Attack/Cyberoam...

Documents

Transcript of Cyberoam Web Application Firewall (WAF) Guideindex-of.es/Attacks/403 Forbidden Attack/Cyberoam...