Cross Site Scripting, splunk.com, XSS, DORK, CWE-79, CAPEC-86

XSS DORK in splunk.com | Vulnerability Crawler Report

Report generated by CloudScan Vulnerability Crawler at Tue Feb 08 13:12:36 CST 2011.

DORK CWE-79 XSS Report

1. Cross-site scripting (reflected)

2. Source code disclosure

3. Cookie scoped to parent domain

4. Cookie without HttpOnly flag set

5. TRACE method is enabled

6. Robots.txt file

1. Cross-site scripting (reflected) next

Summary

Severity:	High
Confidence:	Certain
Host:	http://www.splunk.com
Path:	/

Issue detail

The name of an arbitrarily supplied request parameter is copied into an HTML comment. The payload fee9d--><script>alert(1)</script>08c2823f476 was submitted in the name of an arbitrarily supplied request 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 HTML comment tags does not prevent XSS attacks if the user is able to close the comment or use other techniques to introduce scripts within the comment 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 /?fee9d--><script>alert(1)</script>08c2823f476=1 HTTP/1.1
Host: www.splunk.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
Date: Tue, 08 Feb 2011 18:41:48 GMT
Server: Apache/2.2.8 (EL)
Vary: Host,Accept-Encoding,User-Agent
Set-Cookie: Apache=173.193.214.243.1297190508959980; path=/; expires=Wed, 04-Feb-26 18:41:48 GMT; domain=.splunk.com
X-Powered-By: PHP/5.2.6
Set-Cookie: XARAYASID=uahgvq28houk9cfelpvodilh27; expires=Sat, 09 Feb 2036 00:41:48 GMT; path=/; domain=.splunk.com
Expires: 0
Cache-Control: public, must-revalidate
Pragma:
ETag: b0e1dfbf44786a21b0738d7a8fe36b221297190510
Last-Modified: Tue, 08 Feb 2011 18:41:50 GMT
Connection: close
Content-Type: text/html; charset=utf-8
Content-Length: 55886

<!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" xmlns:dc="http://purl.org/d
...[SNIP]...
<script>alert(1)</script>08c2823f476=1 -->
...[SNIP]...

2. Source code disclosure previous next

Summary

Severity:	Low
Confidence:	Tentative
Host:	http://www.splunk.com
Path:	/

Issue detail

The application appears to disclose some server-side source code written in PHP.

Issue background

Server-side source code may contain sensitive information which can help an attacker formulate attacks against the application.

Issue remediation

Server-side source code is normally disclosed to clients as a result of typographical errors in scripts or because of misconfiguration, such as failing to grant executable permissions to a script or directory. You should review the cause of the code disclosure and prevent it from happening.

Request

GET / HTTP/1.1
Host: www.splunk.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
Date: Tue, 08 Feb 2011 18:41:04 GMT
Server: Apache/2.2.8 (EL)
Vary: Host,Accept-Encoding,User-Agent
Set-Cookie: Apache=173.193.214.243.1297190464067347; path=/; expires=Wed, 04-Feb-26 18:41:04 GMT; domain=.splunk.com
X-Powered-By: PHP/5.2.6
Set-Cookie: XARAYASID=8v5n9h6lp4bg59as6pc0apoi47; expires=Sat, 09 Feb 2036 00:41:04 GMT; path=/; domain=.splunk.com
Expires: 0
Cache-Control: public, must-revalidate
Pragma:
ETag: 3d14396a178718eef57fdbe52275cbdf1297190308
Last-Modified: Tue, 08 Feb 2011 18:38:28 GMT
Connection: close
Content-Type: text/html; charset=UTF-8
Content-Length: 55788

<!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" xmlns:dc="http://purl.org/d
...[SNIP]...
:5px;
}
#quoteItemNav {
   float:left;
   margin-right:8px;
   width:37px;
}
#quoteItemNav a {
   display:block;
   float:right;
   height:20px;
   width:15px;
   margin-top:5px;
   background-image:url(<?= $SrvURL ?>themes/splunk_com/css/images/triangles.gif);
   background-repeat:no-repeat;
}
#quoteItemNav a#quoteItemFwd {
   background-position:-13px 7px;
}
#quoteItemNav a#quoteItemrBack {
   background-positio
...[SNIP]...

3. Cookie scoped to parent domain previous next

Summary

Severity:	Information
Confidence:	Certain
Host:	http://www.splunk.com
Path:	/

Issue detail

The following cookies were issued by the application and is scoped to a parent of the issuing domain:

Apache=173.193.214.243.1297190464067347; path=/; expires=Wed, 04-Feb-26 18:41:04 GMT; domain=.splunk.com
XARAYASID=8v5n9h6lp4bg59as6pc0apoi47; expires=Sat, 09 Feb 2036 00:41:04 GMT; path=/; domain=.splunk.com

The cookies do not appear to contain session tokens, which may reduce the risk associated with this issue. You should review the contents of the cookies to determine their function.

Issue background

A cookie's domain attribute determines which domains can access the cookie. Browsers will automatically submit the cookie in requests to in-scope domains, and those domains will also be able to access the cookie via JavaScript. If a cookie is scoped to a parent domain, then that cookie will be accessible by the parent domain and also by any other subdomains of the parent domain. If the cookie contains sensitive data (such as a session token) then this data may be accessible by less trusted or less secure applications residing at those domains, leading to a security compromise.

Issue remediation

By default, cookies are scoped to the issuing domain and all subdomains. If you remove the explicit domain attribute from your Set-cookie directive, then the cookie will have this default scope, which is safe and appropriate in most situations. If you particularly need a cookie to be accessible by a parent domain, then you should thoroughly review the security of the applications residing on that domain and its subdomains, and confirm that you are willing to trust the people and systems which support those applications.

Request

GET / HTTP/1.1
Host: www.splunk.com
Accept: */*
Accept-Language: en
User-Agent: Mozilla/4.0 (compatible; MSIE 7.0; Windows NT 6.0)
Connection: close

Response

4. Cookie without HttpOnly flag set previous next

Summary

Severity:	Information
Confidence:	Certain
Host:	http://www.splunk.com
Path:	/

Issue detail

The following cookies were issued by the application and do not have the HttpOnly flag set:

Apache=173.193.214.243.1297190464067347; path=/; expires=Wed, 04-Feb-26 18:41:04 GMT; domain=.splunk.com
XARAYASID=8v5n9h6lp4bg59as6pc0apoi47; expires=Sat, 09 Feb 2036 00:41:04 GMT; path=/; domain=.splunk.com

The cookies do not appear to contain session tokens, which may reduce the risk associated with this issue. You should review the contents of the cookies to determine their 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

GET / HTTP/1.1
Host: www.splunk.com
Accept: */*
Accept-Language: en
User-Agent: Mozilla/4.0 (compatible; MSIE 7.0; Windows NT 6.0)
Connection: close

Response

5. TRACE method is enabled previous next

Summary

Severity:	Information
Confidence:	Certain
Host:	http://www.splunk.com
Path:	/

Issue description

The TRACE method is designed for diagnostic purposes. If enabled, the web server will respond to requests which use the TRACE method by echoing in its response the exact request which was received.

Although this behaviour is apparently harmless in itself, it can sometimes be leveraged to support attacks against other application users. If an attacker can find a way of causing a user to make a TRACE request, and can retrieve the response to that request, then the attacker will be able to capture any sensitive data which is included in the request by the user's browser, for example session cookies or credentials for platform-level authentication. This may exacerbate the impact of other vulnerabilities, such as cross-site scripting.

Issue remediation

The TRACE method should be disabled on the web server.

Request

TRACE / HTTP/1.0
Host: www.splunk.com
Cookie: 36abcb3b73dc9e20

Response

HTTP/1.1 200 OK
Date: Tue, 08 Feb 2011 18:41:04 GMT
Server: Apache/2.2.8 (EL)
Vary: Host
Connection: close
Content-Type: message/http

TRACE / HTTP/1.0
Host: www.splunk.com
Cookie: 36abcb3b73dc9e20

6. Robots.txt file previous

Summary

Severity:	Information
Confidence:	Certain
Host:	http://www.splunk.com
Path:	/

Issue detail

The web server contains a robots.txt file.

Issue background

The file robots.txt is used to give instructions to web robots, such as search engine crawlers, about locations within the web site which robots are allowed, or not allowed, to crawl and index.

The presence of the robots.txt does not in itself present any kind of security vulnerability. However, it is often used to identify restricted or private areas of a site's contents. The information in the file may therefore help an attacker to map out the site's contents, especially if some of the locations identified are not linked from elsewhere in the site. If the application relies on robots.txt to protect access to these areas, and does not enforce proper access control over them, then this presents a serious vulnerability.

Issue remediation

The robots.txt file is not itself a security threat, and its correct use can represent good practice for non-security reasons. You should not assume that all web robots will honour the file's instructions. Rather, assume that attackers will pay close attention to any locations identified in the file. Do not rely on robots.txt to provide any kind of protection over unauthorised access.

Request

GET /robots.txt HTTP/1.0
Host: www.splunk.com

Response

HTTP/1.1 200 OK
Date: Tue, 08 Feb 2011 18:41:06 GMT
Server: Apache/2.2.8 (EL)
Vary: Host,Accept-Encoding,User-Agent
Set-Cookie: Apache=173.193.214.243.1297190466444572; path=/; expires=Wed, 04-Feb-26 18:41:06 GMT; domain=.splunk.com
Last-Modified: Wed, 17 Nov 2010 21:45:29 GMT
ETag: "100187-528-4954697827040"
Accept-Ranges: bytes
Content-Length: 1320
Connection: close
Content-Type: text/plain; charset=UTF-8

User-agent: gsa-crawler-splunk # Even tho identical to below, we will continue to keep this section in case we want to add to it
Disallow: /base/index.php # Do not allow index.php with an
...[SNIP]...

Report generated by CloudScan Vulnerability Crawler at Tue Feb 08 13:12:36 CST 2011.