CWE-79: Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting') in randco.fr

Report generated by XSS.CX at Wed Apr 27 07:06:39 CDT 2011.

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

XSS Crawler | SQLi Crawler | HTTPi Crawler | FI Crawler

1. Cross-site scripting (reflected)

2. Cross-domain Referer leakage

2.1. http://www.randco.fr/

2.2. http://www.randco.fr/

2.3. http://www.randco.fr/

3. Cross-domain script include

4. Private IP addresses disclosed

5. Robots.txt file

6. Content type incorrectly stated

1. Cross-site scripting (reflected) next

Summary

Severity:	High
Confidence:	Certain
Host:	http://www.randco.fr
Path:	/

Issue detail

The value of the p request parameter is copied into the value of an HTML tag attribute which is encapsulated in double quotation marks. The payload 1b377"><img%20src%3da%20onerror%3dalert(1)>45ed2872fa2 was submitted in the p parameter. This input was echoed as 1b377\"><img src=a onerror=alert(1)>45ed2872fa2 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 an event handler to introduce arbitrary JavaScript into the document.

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 /?p=contact1b377"><img%20src%3da%20onerror%3dalert(1)>45ed2872fa2 HTTP/1.1
Host: www.randco.fr
Proxy-Connection: keep-alive
Referer: http://www.randco.fr/
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: __utma=112901127.702111400.1303905434.1303905434.1303905434.1; __utmb=112901127; __utmc=112901127; __utmz=112901127.1303905434.1.1.utmccn=(direct)|utmcsr=(direct)|utmcmd=(none)

Response

HTTP/1.1 200 OK
Date: Wed, 27 Apr 2011 11:57:27 GMT
Server: Apache
Content-Length: 5042
Content-Type: text/html

<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Strict//EN"
"http://www.w3.org/TR/xhtml1/DTD/xhtml1-strict.dtd">

<html xmlns="http://www.w3.org/1999/xhtml" xml:lang="fr" lang="fr">
<head>
<title></t
...[SNIP]...
<img src="img/ssmenu-contact1b377\"><img src=a onerror=alert(1)>45ed2872fa2.jpg" width="688" height="200" border="0" alt="" title=""/>
...[SNIP]...

2. Cross-domain Referer leakage previous next
There are 3 instances of this issue:

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.

2.1. http://www.randco.fr/ next

Summary

Severity:	Information
Confidence:	Certain
Host:	http://www.randco.fr
Path:	/

Issue detail

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

http://www.randco.fr/?p=societe

The response contains the following links to other domains:

http://ajax.googleapis.com/ajax/libs/jquery/1.4.2/jquery.min.js
http://ajax.googleapis.com/ajax/libs/jqueryui/1.7.2/jquery-ui.min.js
http://devis.randco.fr/
http://maps.google.fr/maps?f=q&source=embed&hl=fr&geocode=&q=10+Rue+Pergol%C3%A8se,+Paris+75116,+France&sll=48.874821,2.294641&sspn=0.010655,0.027874&gl=fr&g=10+Rue+Pergol%C3%A8se,+Paris+75116,+France&ie=UTF8&hq=&hnear=10+Rue+Pergol%C3%A8se,+75116+Paris,+Ile-de-France&ll=48.877107,2.289705&spn=0.008467,0.012875&z=15
http://maps.google.fr/maps?f=q&source=s_q&hl=fr&geocode=&q=10+Rue+Pergol%C3%A8se,+Paris+75116,+France&sll=48.874821,2.294641&sspn=0.010655,0.027874&gl=fr&g=10+Rue+Pergol%C3%A8se,+Paris+75116,+France&ie=UTF8&hq=&hnear=10+Rue+Pergol%C3%A8se,+75116+Paris,+Ile-de-France&ll=48.877107,2.289705&spn=0.008467,0.012875&z=15&iwloc=&&output=embed
http://maps.google.fr/maps?q=47+avenue+hoche+paris&oe=utf-8&ie=UTF8&hq=&hnear=47+Avenue+Hoche,+75008+Paris,+Ile-de-France&gl=fr&ei=ZHh-S6TWOsrV4gb7xMGvDw&ved=0CAoQ8gEwAA&ll=48.875583,2.298503&spn=0.008468,0.012875&z=15&iwloc=&&output=embed
http://maps.google.fr/maps?q=47+avenue+hoche+paris&oe=utf-8&ie=UTF8&hq=&hnear=47+Avenue+Hoche,+75008+Paris,+Ile-de-France&gl=fr&ei=ZHh-S6TWOsrV4gb7xMGvDw&ved=0CAoQ8gEwAA&ll=48.875583,2.298503&spn=0.008468,0.012875&z=15&source=embed
http://www.google-analytics.com/urchin.js
http://www.nagios.org/support/servicepartners
http://www.webrankinfo.com/annuaire/cat-13496-conseil-en-systemes-d-information.htm
http://www.webrankinfo.com/annuaire/cat-759-cabinets-de-conseil.htm
http://www.webrankinfo.com/annuaire/site-12599.htm
http://www.webrankinfo.com/google/youtube.htm
http://www.webrankinfo.com/images/wri/webrankinfo-80-15.png

Request

GET /?p=societe HTTP/1.1
Host: www.randco.fr
Proxy-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: __utma=112901127.702111400.1303905434.1303905434.1303905434.1; __utmc=112901127; __utmz=112901127.1303905434.1.1.utmccn=(direct)|utmcsr=(direct)|utmcmd=(none); __utmb=112901127

Response

HTTP/1.1 200 OK
Date: Wed, 27 Apr 2011 11:57:43 GMT
Server: Apache
Content-Length: 8688
Content-Type: text/html

<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Strict//EN"
"http://www.w3.org/TR/xhtml1/DTD/xhtml1-strict.dtd">

<html xmlns="http://www.w3.org/1999/xhtml" xml:lang="fr" lang="fr">
   <head>
       <title>Not
...[SNIP]...
<link rel="stylesheet" type="text/css" href="css/stylerandco.css" />
           <script type="text/javascript" src="http://ajax.googleapis.com/ajax/libs/jquery/1.4.2/jquery.min.js"></script>
           <script type="text/javascript" src="http://ajax.googleapis.com/ajax/libs/jqueryui/1.7.2/jquery-ui.min.js"></script>
...[SNIP]...
<li id="none"><a class="transparent" title="Devis Gratuit !" ="target="_BLANK" href="http://devis.randco.fr"></a>
...[SNIP]...
<P>En 2007, notre partenariat avec <A href="http://www.nagios.org/support/servicepartners" target=_blank BORDER="0">Nagios</A>
...[SNIP]...
<BR><IFRAME height=300 marginHeight=0 src="http://maps.google.fr/maps?q=47+avenue+hoche+paris&oe=utf-8&ie=UTF8&hq=&hnear=47+Avenue+Hoche,+75008+Paris,+Ile-de-France&gl=fr&ei=ZHh-S6TWOsrV4gb7xMGvDw&ved=0CAoQ8gEwAA&ll=48.875583,2.298503&spn=0.008468,0.012875&z=15&iwloc=&&output=embed" frameBorder=0 width=300 marginWidth=0 scrolling=no></IFRAME><BR><SMALL><A style="TEXT-ALIGN: left; COLOR: #0000ff" href="http://maps.google.fr/maps?q=47+avenue+hoche+paris&oe=utf-8&ie=UTF8&hq=&hnear=47+Avenue+Hoche,+75008+Paris,+Ile-de-France&gl=fr&ei=ZHh-S6TWOsrV4gb7xMGvDw&ved=0CAoQ8gEwAA&ll=48.875583,2.298503&spn=0.008468,0.012875&z=15&source=embed">Agrandir le plan</A>
...[SNIP]...
<BR><IFRAME height=300 marginHeight=0 src="http://maps.google.fr/maps?f=q&source=s_q&hl=fr&geocode=&q=10+Rue+Pergol%C3%A8se,+Paris+75116,+France&sll=48.874821,2.294641&sspn=0.010655,0.027874&gl=fr&g=10+Rue+Pergol%C3%A8se,+Paris+75116,+France&ie=UTF8&hq=&hnear=10+Rue+Pergol%C3%A8se,+75116+Paris,+Ile-de-France&ll=48.877107,2.289705&spn=0.008467,0.012875&z=15&iwloc=&&output=embed" frameBorder=0 width=300 marginWidth=0 scrolling=no></IFRAME><BR><SMALL><A style="TEXT-ALIGN: left; COLOR: #0000ff" href="http://maps.google.fr/maps?f=q&source=embed&hl=fr&geocode=&q=10+Rue+Pergol%C3%A8se,+Paris+75116,+France&sll=48.874821,2.294641&sspn=0.010655,0.027874&gl=fr&g=10+Rue+Pergol%C3%A8se,+Paris+75116,+France&ie=UTF8&hq=&hnear=10+Rue+Pergol%C3%A8se,+75116+Paris,+Ile-de-France&ll=48.877107,2.289705&spn=0.008467,0.012875&z=15">Agrandir le plan</A>
...[SNIP]...
<p>Notre site <a href="http://www.webrankinfo.com/annuaire/site-12599.htm">Cabinet de Conseil en Informatique RANDCO</a> est list. dans la cat.gorie <a href="http://www.webrankinfo.com/annuaire/cat-759-cabinets-de-conseil.htm">
Cabinets de conseil</a> :
<a href="http://www.webrankinfo.com/annuaire/cat-13496-conseil-en-systemes-d-information.htm">
Conseil IT</a> de l'annuaire <a href="http://www.webrankinfo.com/google/youtube.htm"><img src="http://www.webrankinfo.com/images/wri/webrankinfo-80-15.png" title="WebRankInfo" width="80" height="15" alt="Le site de partage de video" /></a>
...[SNIP]...


<script src="http://www.google-analytics.com/urchin.js" type="text/javascript"></script>
...[SNIP]...

2.2. http://www.randco.fr/ previous next

Summary

Severity:	Information
Confidence:	Certain
Host:	http://www.randco.fr
Path:	/

Issue detail

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

http://www.randco.fr/?

The response contains the following links to other domains:

http://ajax.googleapis.com/ajax/libs/jquery/1.4.2/jquery.min.js
http://ajax.googleapis.com/ajax/libs/jqueryui/1.7.2/jquery-ui.min.js
http://blog.randco.fr/
http://devis.randco.fr/
http://twitter.com/randcofr
http://www.google-analytics.com/urchin.js

Request

GET /? HTTP/1.1
Host: www.randco.fr
Proxy-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: __utma=112901127.702111400.1303905434.1303905434.1303905434.1; __utmc=112901127; __utmz=112901127.1303905434.1.1.utmccn=(direct)|utmcsr=(direct)|utmcmd=(none); __utmb=112901127

Response

HTTP/1.1 200 OK
Date: Wed, 27 Apr 2011 11:57:48 GMT
Server: Apache
Content-Length: 14199
Content-Type: text/html

<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Strict//EN"
"http://www.w3.org/TR/xhtml1/DTD/xhtml1-strict.dtd">

<html xmlns="http://www.w3.org/1999/xhtml" xml:lang="fr" lang="fr">
   <head>
       <title>Ran
...[SNIP]...
<link rel="stylesheet" type="text/css" href="css/stylerandco.css" />
           <script type="text/javascript" src="http://ajax.googleapis.com/ajax/libs/jquery/1.4.2/jquery.min.js"></script>
           <script type="text/javascript" src="http://ajax.googleapis.com/ajax/libs/jqueryui/1.7.2/jquery-ui.min.js"></script>
...[SNIP]...
<li id="none"><a class="transparent" title="Devis Gratuit !" ="target="_BLANK" href="http://devis.randco.fr"></a>
...[SNIP]...
<div id="actu2">

       <a href="http://twitter.com/randcofr" target="_blank"><img src="img/twitter.jpg" alt="Twitter" title="Twitter" width="30" height="30"></a>
       <a href="http://blog.randco.fr/" target="_blank"><img src="img/blogger-gris.png" alt="Notre blog" title="Notre blog" width="30" height="30">
...[SNIP]...


<script src="http://www.google-analytics.com/urchin.js" type="text/javascript"></script>
...[SNIP]...

2.3. http://www.randco.fr/ previous

Summary

Severity:	Information
Confidence:	Certain
Host:	http://www.randco.fr
Path:	/

Issue detail

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

http://www.randco.fr/?p=actualites&ID=27

The response contains the following links to other domains:

http://ajax.googleapis.com/ajax/libs/jquery/1.4.2/jquery.min.js
http://ajax.googleapis.com/ajax/libs/jqueryui/1.7.2/jquery-ui.min.js
http://devis.randco.fr/
http://www.google-analytics.com/urchin.js
http://www.twitter.com/randcofr

Request

GET /?p=actualites&ID=27 HTTP/1.1
Host: www.randco.fr
Proxy-Connection: keep-alive
Referer: http://www.randco.fr/?p=formation
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: __utma=112901127.702111400.1303905434.1303905434.1303905434.1; __utmc=112901127; __utmz=112901127.1303905434.1.1.utmccn=(direct)|utmcsr=(direct)|utmcmd=(none); __utmb=112901127

Response

HTTP/1.1 200 OK
Date: Wed, 27 Apr 2011 11:57:27 GMT
Server: Apache
Content-Length: 19407
Content-Type: text/html

<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Strict//EN"
"http://www.w3.org/TR/xhtml1/DTD/xhtml1-strict.dtd">

<html xmlns="http://www.w3.org/1999/xhtml" xml:lang="fr" lang="fr">
   <head>
       <title>Art
...[SNIP]...
<link rel="stylesheet" type="text/css" href="css/stylerandco.css" />
           <script type="text/javascript" src="http://ajax.googleapis.com/ajax/libs/jquery/1.4.2/jquery.min.js"></script>
           <script type="text/javascript" src="http://ajax.googleapis.com/ajax/libs/jqueryui/1.7.2/jquery-ui.min.js"></script>
...[SNIP]...
<li id="none"><a class="transparent" title="Devis Gratuit !" ="target="_BLANK" href="http://devis.randco.fr"></a>
...[SNIP]...
</A>ou sur <A href="http://www.twitter.com/randcofr" target=_blank BORDER="0">Twitter</A>
...[SNIP]...


<script src="http://www.google-analytics.com/urchin.js" type="text/javascript"></script>
...[SNIP]...

3. Cross-domain script include previous next

Summary

Severity:	Information
Confidence:	Certain
Host:	http://www.randco.fr
Path:	/

Issue detail

The response dynamically includes the following scripts from other domains:

http://ajax.googleapis.com/ajax/libs/jquery/1.4.2/jquery.min.js
http://ajax.googleapis.com/ajax/libs/jqueryui/1.7.2/jquery-ui.min.js
http://www.google-analytics.com/urchin.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

GET / HTTP/1.1
Host: www.randco.fr
Proxy-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

Response

HTTP/1.1 200 OK
Date: Wed, 27 Apr 2011 11:56:59 GMT
Server: Apache
Content-Length: 14199
Content-Type: text/html

<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Strict//EN"
"http://www.w3.org/TR/xhtml1/DTD/xhtml1-strict.dtd">

<html xmlns="http://www.w3.org/1999/xhtml" xml:lang="fr" lang="fr">
   <head>
       <title>Ran
...[SNIP]...
<link rel="stylesheet" type="text/css" href="css/stylerandco.css" />
           <script type="text/javascript" src="http://ajax.googleapis.com/ajax/libs/jquery/1.4.2/jquery.min.js"></script>
           <script type="text/javascript" src="http://ajax.googleapis.com/ajax/libs/jqueryui/1.7.2/jquery-ui.min.js"></script>
...[SNIP]...


<script src="http://www.google-analytics.com/urchin.js" type="text/javascript"></script>
...[SNIP]...

4. Private IP addresses disclosed previous next

Summary

Severity:	Information
Confidence:	Certain
Host:	http://www.randco.fr
Path:	/

Issue detail

The following RFC 1918 IP address was disclosed in the response:

172.31.252.31

Issue background

RFC 1918 specifies ranges of IP addresses that are reserved for use in private networks and cannot be routed on the public Internet. Although various methods exist by which an attacker can determine the public IP addresses in use by an organisation, the private addresses used internally cannot usually be determined in the same ways.

Discovering the private addresses used within an organisation can help an attacker in carrying out network-layer attacks aiming to penetrate the organisation's internal infrastructure.

Issue remediation

There is not usually any good reason to disclose the internal IP addresses used within an organisation's infrastructure. If these are being returned in service banners or debug messages, then the relevant services should be configured to mask the private addresses. If they are being used to track back-end servers for load balancing purposes, then the addresses should be rewritten with innocuous identifiers from which an attacker cannot infer any useful information about the infrastructure.

Request

Response

5. Robots.txt file previous next

Summary

Severity:	Information
Confidence:	Certain
Host:	http://www.randco.fr
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.randco.fr

Response

HTTP/1.1 200 OK
Date: Wed, 27 Apr 2011 11:57:00 GMT
Server: Apache
Last-Modified: Fri, 09 Feb 2007 21:51:17 GMT
ETag: "6817e-127-4291228c51f40"
Accept-Ranges: bytes
Content-Length: 295
Connection: close
Content-Type: text/plain

# exclude help system from robots
User-agent: *
Disallow: /addon-modules/
Disallow: /doc/
Disallow: /images/
# same idea here...
Disallow: /Depot/
Disallow: /admin/
# but allow htdig to index our doc-
...[SNIP]...

6. Content type incorrectly stated previous

Summary

Severity:	Information
Confidence:	Firm
Host:	http://www.randco.fr
Path:	/img/sponsors/bergame.png

Issue detail

The response contains the following Content-type statement:

Content-Type: image/png

The response states that it contains a PNG image. However, it actually appears to contain a JPEG image.

Issue background

If a web response specifies an incorrect content type, then browsers may process the response in unexpected ways. If the specified content type is a renderable text-based format, then the browser will usually attempt to parse and render the response in that format. If the specified type is an image format, then the browser will usually detect the anomaly and will analyse the actual content and attempt to determine its MIME type. Either case can lead to unexpected results, and if the content contains any user-controllable data may lead to cross-site scripting or other client-side vulnerabilities.

In most cases, the presence of an incorrect content type statement 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 a message body, the application should include a single Content-type header which correctly and unambiguously states the MIME type of the content in the response body.

Request

GET /img/sponsors/bergame.png HTTP/1.1
Host: www.randco.fr
Proxy-Connection: keep-alive
Referer: http://www.randco.fr/
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: */*
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

Response

HTTP/1.1 200 OK
Date: Wed, 27 Apr 2011 11:57:11 GMT
Server: Apache
Last-Modified: Mon, 26 Apr 2010 15:02:09 GMT
ETag: "42cf-f44-485250f9bde40"
Accept-Ranges: bytes
Content-Length: 3908
Content-Type: image/png

......JFIF.....d.d.....hExif..MM.*.................>...........F.(...........1.........N.......d.......d....Paint.NET v3.5.5.....C.................................... . ..
...

...... ...........C.
...[SNIP]...

Report generated by XSS.CX at Wed Apr 27 07:06:39 CDT 2011.