XSS, Reflected Cross Site Scripting, CWE-79, CAPEC-86, DORK, GHDB, olt.custhelp.com

Hoyt LLC Research investigates and reports on security vulnerabilities embedded in Web Applications and Products used in wide-scale deployment.

Report generated by XSS.CX at Fri Apr 29 17:05:59 CDT 2011.

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

1. Cross-site scripting (reflected)

2. Password field with autocomplete enabled

3. SSL cookie without secure flag set

4. Cross-domain Referer leakage

5. Cookie without HttpOnly flag set

1. Cross-site scripting (reflected) next

Summary

Severity:	High
Confidence:	Certain
Host:	https://olt.custhelp.com
Path:	/cgi-bin/olt.cfg/php/enduser/acct_login.php

Issue detail

The value of the OLTSite request parameter is copied into the value of an HTML tag attribute which is encapsulated in double quotation marks. The payload 6fa54"style%3d"x%3aexpression(alert(1))"b886bd6f3e was submitted in the OLTSite parameter. This input was echoed as 6fa54"style="x:expression(alert(1))"b886bd6f3e 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 arbirary 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 /cgi-bin/olt.cfg/php/enduser/acct_login.php?OLTSite=%22%20stYle=x:expre/**/ssion(netsparker(9))%20ns=%22%206fa54"style%3d"x%3aexpression(alert(1))"b886bd6f3e&p_sid=TyYLtJsk&p_accessibility=0&p_redirect=3&p_next_page=acct_login.php HTTP/1.1
Host: olt.custhelp.com
Connection: keep-alive
User-Agent: Mozilla/5.0 (Windows; U; Windows NT 6.1; en-US) AppleWebKit/534.16 (KHTML, like Gecko) Chrome/10.0.648.205 Safari/534.16
Accept: application/xml,application/xhtml+xml,text/html;q=0.9,text/plain;q=0.8,image/png,*/*;q=0.5
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: __utmz=162278755.1304039398.1.1.utmcsr=qriocity.com|utmccn=(referral)|utmcmd=referral|utmcct=/us/en/; __utma=162278755.897277051.1304039398.1304039398.1304039398.1

Response

HTTP/1.1 200 OK
Date: Fri, 29 Apr 2011 21:20:49 GMT
Server: Apache
P3P: policyref="https://olt.custhelp.com/rnt/rnw/p3p/rnw_p3p_ref.xml",CP="CAO CURa ADMa DEVa OUR BUS IND UNI COM NAV"
Set-Cookie: rnw_enduser_login_start=LOGIN_START; expires=Fri, 29-Apr-2011 21:40:49 GMT
RNT-Time: D=69577 t=1304112049847679
RNT-Machine: 02
Vary: Accept-Encoding
X-Cnection: close
Content-Type: text/html; charset=UTF-8
Content-Length: 12015

<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd">
<html lang="en_US">

...[SNIP]...
<a class="tab" name=" answers _tab_link" href="std_alp.php?OLTSite=" stYle=x:expre/**/ssion(netsparker(9)) ns=" 6fa54"style="x:expression(alert(1))"b886bd6f3e&p_sid=cYoJIJsk&p_accessibility=0&p_redirect=3">
...[SNIP]...

2. Password field with autocomplete enabled previous next

Summary

Severity:	Low
Confidence:	Certain
Host:	https://olt.custhelp.com
Path:	/cgi-bin/olt.cfg/php/enduser/acct_login.php

Issue detail

The page contains a form with the following action URL:

https://olt.custhelp.com/cgi-bin/olt.cfg/php/enduser/acct_login_submit.php

The form contains the following password field with autocomplete enabled:

p_passwd

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 /cgi-bin/olt.cfg/php/enduser/acct_login.php?OLTSite=%22%20stYle=x:expre/**/ssion(netsparker(9))%20ns=%22%20&p_sid=TyYLtJsk&p_accessibility=0&p_redirect=3&p_next_page=acct_login.php HTTP/1.1
Host: olt.custhelp.com
Connection: keep-alive
User-Agent: Mozilla/5.0 (Windows; U; Windows NT 6.1; en-US) AppleWebKit/534.16 (KHTML, like Gecko) Chrome/10.0.648.205 Safari/534.16
Accept: application/xml,application/xhtml+xml,text/html;q=0.9,text/plain;q=0.8,image/png,*/*;q=0.5
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: __utmz=162278755.1304039398.1.1.utmcsr=qriocity.com|utmccn=(referral)|utmcmd=referral|utmcct=/us/en/; __utma=162278755.897277051.1304039398.1304039398.1304039398.1

Response

3. SSL cookie without secure flag set previous next

Summary

Severity:	Information
Confidence:	Certain
Host:	https://olt.custhelp.com
Path:	/cgi-bin/olt.cfg/php/enduser/acct_login.php

Issue detail

The following cookie was issued by the application and does not have the secure flag set:

rnw_enduser_login_start=LOGIN_START; expires=Fri, 29-Apr-2011 21:39:11 GMT

The cookie does not appear to contain a session token, which may reduce the risk associated with this issue. You should review the contents of the cookie to determine its function.

Issue background

If the secure flag is set on a cookie, then browsers will not submit the cookie in any requests that use an unencrypted HTTP connection, thereby preventing the cookie from being trivially intercepted by an attacker monitoring network traffic. If the secure flag is not set, then the cookie will be transmitted in clear-text if the user visits any HTTP URLs within the cookie's scope. An attacker may be able to induce this event by feeding a user suitable links, either directly or via another web site. Even if the domain which issued the cookie does not host any content that is accessed over HTTP, an attacker may be able to use links of the form http://example.com:443/ to perform the same attack.

Issue remediation

The secure flag should be set on all cookies that are used for transmitting sensitive data when accessing content over HTTPS. If cookies are used to transmit session tokens, then areas of the application that are accessed over HTTPS should employ their own session handling mechanism, and the session tokens used should never be transmitted over unencrypted communications.

Request

Response

4. Cross-domain Referer leakage previous next

Summary

Severity:	Information
Confidence:	Certain
Host:	https://olt.custhelp.com
Path:	/cgi-bin/olt.cfg/php/enduser/acct_login.php

Issue detail

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

https://olt.custhelp.com/cgi-bin/olt.cfg/php/enduser/acct_login.php?OLTSite=%22%20stYle=x:expre/**/ssion(netsparker(9))%20ns=%22%20&p_sid=TyYLtJsk&p_accessibility=0&p_redirect=3&p_next_page=acct_login.php

The response contains the following links to other domains:

https://www.olt.com/main/home/about.asp
https://www.olt.com/main/home/default.asp
https://www.olt.com/main/home/disclaimer.asp
https://www.olt.com/main/home/getstarted.asp
https://www.olt.com/main/home/images/hdr-logo-home.gif
https://www.olt.com/main/home/images/hdr-slogan.gif
https://www.olt.com/main/home/images/spacer.gif
https://www.olt.com/main/home/payment.asp
https://www.olt.com/main/home/privacysecurity.asp
https://www.olt.com/main/home/products.asp
https://www.olt.com/main/home/service.asp
https://www.olt.com/main/home/sitemap.asp
https://www.olt.com/main/home/states.asp
https://www.olt.com/main/home/styles.css
https://www.olt.com/main/home/taxcorner.asp

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
Date: Fri, 29 Apr 2011 21:19:11 GMT
Server: Apache
P3P: policyref="https://olt.custhelp.com/rnt/rnw/p3p/rnw_p3p_ref.xml",CP="CAO CURa ADMa DEVa OUR BUS IND UNI COM NAV"
Set-Cookie: rnw_enduser_login_start=LOGIN_START; expires=Fri, 29-Apr-2011 21:39:11 GMT
RNT-Time: D=82489 t=1304111951723725
RNT-Machine: 01
Vary: Accept-Encoding
X-Cnection: close
Content-Type: text/html; charset=UTF-8
Content-Length: 11770

<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd">
<html lang="en_US">

...[SNIP]...
<meta name="robots" content="noindex,nofollow">
<link rel="stylesheet" type="text/css" href="https://www.olt.com/main/home/styles.css" />
<link rel="stylesheet" type="text/css" href="/rnt/rnw/css/enduser.css">
...[SNIP]...
<td rowSpan="2"><img height="95" src="https://www.olt.com/main/home/images/spacer.gif" width="10"></td>
            <td rowSpan="2"><img src="https://www.olt.com/main/home/images/hdr-logo-home.gif" alt="Online Taxes OLT Logo" title="Online Taxes OLT Logo" width="200" height="95"></td>
            <td align="right" width="100%"><img src="https://www.olt.com/main/home/images/hdr-slogan.gif" alt="Online Taxes slogan - Simple fast Secure" title="Online Taxes Slogan - Simple Fast Accurate" width="175" height="40"></td>
            <td><img height="40" src="https://www.olt.com/main/home/images/spacer.gif" width="10"></td>
...[SNIP]...
<nobr><a href="https://www.olt.com/main/home/default.asp">Home</a>
             |  <a href="https://www.olt.com/main/home/about.asp">About Us</a>  |  <a href="https://www.olt.com/main/home/products.asp">Products</a>
             |  <a href="https://www.olt.com/main/home/service.asp">Customer Service</a>  |  <a href="https://www.olt.com/main/home/states.asp">States</a>
             |  <a href="https://www.olt.com/main/home/taxcorner.asp">Tax Corner</a>
...[SNIP]...
<td><img height="55" src="https://www.olt.com/main/home/images/spacer.gif" width="10"></td>
...[SNIP]...
<div class="foot">
               <a href="https://www.olt.com/main/home/default.asp">Home</a> |
               <a href="https://www.olt.com/main/home/about.asp">About Us</a> |
               <a href="https://www.olt.com/main/home/payment.asp">Payment Options</a> |
               <a href="https://www.olt.com/main/home/service.asp">Customer Service</a> |
               <a href="https://www.olt.com/main/home/states.asp">States</a> |
               <a href="https://www.olt.com/main/home/getstarted.asp">Get Started</a>
...[SNIP]...
<div class="tiny">
   <a href="https://www.olt.com/main/home/privacysecurity.asp">Privacy/Security</a> |
   <a href="https://www.olt.com/main/home/disclaimer.asp">Disclaimer/Terms Of Use</a> |
   <a href="https://www.olt.com/main/home/sitemap.asp">Site Map</a>
...[SNIP]...

5. Cookie without HttpOnly flag set previous

Summary

Severity:	Information
Confidence:	Certain
Host:	https://olt.custhelp.com
Path:	/cgi-bin/olt.cfg/php/enduser/acct_login.php

Issue detail

The following cookie was issued by the application and does not have the HttpOnly flag set:

rnw_enduser_login_start=LOGIN_START; expires=Fri, 29-Apr-2011 21:39:11 GMT

The cookie does not appear to contain a session token, which may reduce the risk associated with this issue. You should review the contents of the cookie to determine its function.

Issue background

If the HttpOnly attribute is set on a cookie, then the cookie's value cannot be read or set by client-side JavaScript. This measure can prevent certain client-side attacks, such as cross-site scripting, from trivially capturing the cookie's value via an injected script.

Issue remediation

There is usually no good reason not to set the HttpOnly flag on all cookies. Unless you specifically require legitimate client-side scripts within your application to read or set a cookie's value, you should set the HttpOnly flag by including this attribute within the relevant Set-cookie directive.

You should be aware that the restrictions imposed by the HttpOnly flag can potentially be circumvented in some circumstances, and that numerous other serious attacks can be delivered by client-side script injection, aside from simple cookie stealing.

Request

Response

Report generated by XSS.CX at Fri Apr 29 17:05:59 CDT 2011.