Report generated by XSS.CX at Sun Nov 21 15:29:20 CST 2010.

Cross Site Scripting Reports | Hoyt LLC Research

1. Cross-site scripting (reflected) next

Summary

Severity:	High
Confidence:	Certain
Host:	https://4qinvite.4q.iperceptions.com
Path:	/1.aspx

Issue detail

The value of the sdfc request parameter is copied into a JavaScript string which is encapsulated in single quotation marks. The payload 23d3f'-alert(1)-'3687970a447 was submitted in the sdfc parameter. This input was echoed unmodified in the application's response.

This proof-of-concept attack demonstrates that it is possible to inject arbitrary JavaScript into the application's response.

Remediation detail

Echoing user-controllable data within a script context is inherently dangerous and can make XSS attacks difficult to prevent. If at all possible, the application should avoid echoing user data within this context.

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.

Remediation background

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

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 /1.aspx?sdfc=299f610e-24038-38153450-25fe-438c-8517-2aca3243ff7523d3f'-alert(1)-'3687970a447&lID=1&loc=4Q-WEB2 HTTP/1.1
Host: 4qinvite.4q.iperceptions.com
Accept: */*
Accept-Language: en
User-Agent: Mozilla/4.0 (compatible; MSIE 7.0; Windows NT 6.0)
Connection: close

Response

HTTP/1.1 200 OK
Connection: close
Date: Sun, 21 Nov 2010 17:17:11 GMT
Server: Microsoft-IIS/6.0
X-Powered-By: ASP.NET
X-Srv-By: 4Q-INVITE2
X-AspNet-Version: 2.0.50727
Set-Cookie: ASP.NET_SessionId=auwb01i1a2g3ks3mlhwi5jmt; path=/; HttpOnly
Cache-Control: private
Content-Type: text/html; charset=utf-8
Content-Length: 1089

var sID= '24038'; var sC= 'IPE24038'; var brow= 'IE'; var vers= '7.0'; var lID= '1'; var loc= '4Q-WEB2'; var ps= 'sdfc=299f610e-24038-38153450-25fe-438c-8517-2aca3243ff7523d3f'-alert(1)-'3687970a447&lID=1&loc=4Q-WEB2';var sGA='';function setupGA(url) { return url;}var tC= 'IPEt'; var tCv='?'; CCook(tC,tC,0); tCv= GetC(tC);if (GetC(sC)==null && tCv != null) {CCook(sC,sC,30); Ld();} DCook(tC);funct
...[SNIP]...

2. SSL cookie without secure flag set previous

Summary

Severity:	Medium
Confidence:	Firm
Host:	https://4qinvite.4q.iperceptions.com
Path:	/1.aspx

Issue detail

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

ASP.NET_SessionId=cmqew5u3rnfod155uppd5re4; path=/; HttpOnly

The cookie appears to contain a session token, which may increase 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

POST /1.aspx?sdfc=299f610e-24038-38153450-25fe-438c-8517-2aca3243ff7523d3f'-alert(1)-'3687970a447&lID=1&loc=4Q-WEB2 HTTP/1.1
Accept: image/jpeg, image/gif, image/pjpeg, application/x-ms-application, application/xaml+xml, application/x-ms-xbap, */*
User-Agent: Mozilla/4.0 (compatible; MSIE 8.0; Windows NT 6.1; WOW64; Trident/4.0; SLCC2; .NET CLR 2.0.50727; .NET CLR 3.5.30729; .NET CLR 3.0.30729; .NET4.0C; .NET4.0E)
Content-Type: application/x-www-form-urlencoded
Accept-Encoding: gzip, deflate
Accept-Language: en-US
Host: 4qinvite.4q.iperceptions.com
Connection: Keep-Alive
Cache-Control: no-cache
Content-Length: 48

button=show+response&renderableItem=%2Fshow%2F13

Response

HTTP/1.1 200 OK
Date: Sun, 21 Nov 2010 18:58:25 GMT
Server: Microsoft-IIS/6.0
X-Powered-By: ASP.NET
X-Srv-By: 4Q-INVITE2
X-AspNet-Version: 2.0.50727
Set-Cookie: ASP.NET_SessionId=cmqew5u3rnfod155uppd5re4; path=/; HttpOnly
Cache-Control: private
Content-Length: 0

Report generated by XSS.CX at Sun Nov 21 15:29:20 CST 2010.