XSS, Reflected Cross Site Scripting, CWE-79, CAPEC-86, DORK, GHDB, secure.istockphoto.com

Report generated by XSS.CX at Sat Aug 20 07:23:42 GMT-06:00 2011.

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

1. Cross-site scripting (reflected)

XSS in secure.istockphoto.com, XSS, DORK, GHDB, Cross Site Scripting, CWE-79, CAPEC-86

2. Flash cross-domain policy

3. Password field with autocomplete enabled

4. Referer-dependent response

5. Cross-domain script include

6. Robots.txt file

7. SSL certificate

1. Cross-site scripting (reflected) next

Summary

Severity:	High
Confidence:	Certain
Host:	https://secure.istockphoto.com
Path:	/signup

Issue detail

The value of the leftSide%5BloginInfo%5D%5Bcountry%5D request parameter is copied into the HTML document as plain text between tags. The payload %0029d70<script>alert(1)</script>2d2f7c3f698 was submitted in the leftSide%5BloginInfo%5D%5Bcountry%5D parameter. This input was echoed as 29d70<script>alert(1)</script>2d2f7c3f698 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 application attempts to block certain characters that are often used in XSS attacks but this can be circumvented by submitting a URL-encoded NULL byte (%00) anywhere before the characters that are being blocked.

Remediation detail

NULL byte bypasses typically arise when the application is being defended by a web application firewall (WAF) that is written in native code, where strings are terminated by a NULL byte. You should fix the actual vulnerability within the application code, and if appropriate ask your WAF vendor to provide a fix for the NULL byte bypass.

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 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

POST /signup HTTP/1.1
Host: secure.istockphoto.com
User-Agent: Mozilla/5.0 (Windows; U; Windows NT 6.1; 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
Connection: keep-alive
Referer: http://www.istockphoto.com/signup
Cookie: iStockSession=2cc7699782db9292993592db651144e7; SSLB=B; __utma=1.648264806.1313846141.1313846141.1313846141.1; __utmb=1.4.10.1313846141; __utmc=1; __utmz=1.1313846141.1.1.utmcsr=fakereferrerdominator.com|utmccn=(referral)|utmcmd=referral|utmcct=/referrerPathName; __utmv=1.guest; s_cc=true; s_visit=1; ttc=1313846141931; gpv_07=iStock%7CMyAccount%7CSignUpStep1; undefined_s=First%20Visit; s_vnum=1314853200934%26vn%3D1; s_invisit=true; s_nr=1313846176999-New; s_sq=gettyistockphotoprod%3D%2526pid%253DiStock%25257CMyAccount%25257CSignUpStep1%2526pidt%253D1%2526oid%253DNext%252520Step%2526oidt%253D3%2526ot%253DSUBMIT; s_vi=[CS]v1|2727D9BA050125EE-60000108E02D8513[CE]
Content-Type: application/x-www-form-urlencoded
Content-Length: 611

signupFormtoken=YToxOntzOjU6InRva2VuIjtzOjMyOiI2MGIwYzgzYzFlMGU3OWMzNjk3Nzg3M2QyNDUwOWIyOSI7fQ%3D%3D&leftSide%5BloginInfo%5D%5Bemail%5D=&leftSide%5BloginInfo%5D%5BmemberName%5D=&leftSide%5BloginInfo%5D%5Bpassword%5D=&leftSide%5BloginInfo%5D%5Bconfirmpassword%5D=&leftSide%5BloginInfo%5D%5Bcountry%5D=%0029d70<script>alert(1)</script>2d2f7c3f698&leftSide%5BmemberAgreement%5D%5BagreementCheckboxmainOptIn%5D=0&leftSide%5BmemberAgreement%5D%5BagreementCheckboxmainOptIn%5D=1&rightSide%5BemailOptions%5D%5BcontactSheet%5D=0&rightSide%5BemailOption
...[SNIP]...

Response

HTTP/1.1 200 OK
Server: Apache
X-Cnection: close
Content-Type: text/html; charset=utf-8
Vary: Accept-Encoding
Content-Length: 27204
Date: Sat, 20 Aug 2011 13:18:51 GMT
Connection: keep-alive
Cache-Control: no-store, no-cache, must-revalidate, post-check=0, pre-check=0
Expires: Thu, 19 Nov 1981 08:52:00 GMT
Pragma: no-cache

<!DOCTYPE html><html><head><meta charset="utf-8">
<meta name="keywords" content="stock photography, stock agency, photos, digital stock, royalty free" >
<meta name="description" content="Browse the be
...[SNIP]...
<p>'\029d70<script>alert(1)</script>2d2f7c3f698' was not found in the haystack</p>
...[SNIP]...

2. Flash cross-domain policy previous next

Summary

Severity:	Low
Confidence:	Certain
Host:	https://secure.istockphoto.com
Path:	/crossdomain.xml

Issue detail

The application publishes a Flash cross-domain policy which uses a wildcard to specify allowed domains.

Using a wildcard to specify allowed domains means that any domain matching the wildcard expression can perform two-way interaction with this application. You should only use this policy if you fully trust every possible web site that may reside on a domain which matches the wildcard expression.

Issue background

The Flash cross-domain policy controls whether Flash client components running on other domains can perform two-way interaction with the domain which publishes the policy. If another domain is allowed by the policy, then that domain can potentially attack users of the application. If a user is logged in to the application, and visits a domain allowed by the policy, then any malicious content running on that domain can potentially gain full access to the application within the security context of the logged in user.

Even if an allowed domain is not overtly malicious in itself, security vulnerabilities within that domain could potentially be leveraged by a third-party attacker to exploit the trust relationship and attack the application which allows access.

Issue remediation

You should review the domains which are allowed by the Flash cross-domain policy and determine whether it is appropriate for the application to fully trust both the intentions and security posture of those domains.

Request

GET /crossdomain.xml HTTP/1.0
Host: secure.istockphoto.com

Response

HTTP/1.0 200 OK
Content-Type: text/x-cross-domain-policy
Server: BigIP
Content-Length: 286
Date: Sat, 20 Aug 2011 13:16:20 GMT
Connection: close

<?xml version="1.0"?> <!DOCTYPE cross-domain-policy SYSTEM "http://www.macromedia.com/xml/dtds/cross-domain-policy.dtd"> <cross-domain-policy> <site-control permitted-cross-domain-policies="by-cont
...[SNIP]...
<allow-access-from domain="*.istockphoto.com" />
...[SNIP]...

3. Password field with autocomplete enabled previous next

Summary

Severity:	Low
Confidence:	Certain
Host:	https://secure.istockphoto.com
Path:	/signup

Issue detail

The page contains a form with the following action URL:

https://secure.istockphoto.com/signup

The form contains the following password fields with autocomplete enabled:

leftSide[loginInfo][password]
leftSide[loginInfo][confirmpassword]

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

Response

4. Referer-dependent response previous next

Summary

Severity:	Information
Confidence:	Firm
Host:	https://secure.istockphoto.com
Path:	/signup

Issue description

The application's responses appear to depend systematically on the presence or absence of the Referer header in requests. This behaviour does not necessarily constitute a security vulnerability, and you should investigate the nature of and reason for the differential responses to determine whether a vulnerability is present.

Common explanations for Referer-dependent responses include:

Referer-based access controls, where the application assumes that if you have arrived from one privileged location then you are authorised to access another privileged location. These controls can be trivially defeated by supplying an accepted Referer header in requests for the vulnerable function.
Attempts to prevent cross-site request forgery attacks by verifying that requests to perform privileged actions originated from within the application itself and not from some external location. Such defences are not robust - methods have existed through which an attacker can forge or mask the Referer header contained within a target user's requests, by leveraging client-side technologies such as Flash and other techniques.
Delivery of Referer-tailored content, such as welcome messages to visitors from specific domains, search-engine optimisation (SEO) techniques, and other ways of tailoring the user's experience. Such behaviours often have no security impact; however, unsafe processing of the Referer header may introduce vulnerabilities such as SQL injection and cross-site scripting. If parts of the document (such as META keywords) are updated based on search engine queries contained in the Referer header, then the application may be vulnerable to persistent code injection attacks, in which search terms are manipulated to cause malicious content to appear in responses served to other application users.

Issue remediation

The Referer header is not a robust foundation on which to build any security measures, such as access controls or defences against cross-site request forgery. Any such measures should be replaced with more secure alternatives that are not vulnerable to Referer spoofing.

If the contents of responses is updated based on Referer data, then the same defences against malicious input should be employed here as for any other kinds of user-supplied data.

Request 1

Response 1

HTTP/1.1 200 OK
Server: Apache
X-Cnection: close
Content-Type: text/html; charset=utf-8
Vary: Accept-Encoding
Content-Length: 27057
Date: Sat, 20 Aug 2011 13:16:19 GMT
Connection: keep-alive
Cache-Control: no-store, no-cache, must-revalidate, post-check=0, pre-check=0
Expires: Thu, 19 Nov 1981 08:52:00 GMT
Pragma: no-cache

<!DOCTYPE html><html><head><meta charset="utf-8">
<meta name="keywords" content="stock photography, stock agency, photos, digital stock, royalty free" >
<meta name="description" content="Browse the be
...[SNIP]...

</script><script type="text/javascript">
//
</script>
<script type="text/javascript">
//<!--

var lpLanguage = 'english';
var lpUnit = 'istock';
var lpLoginFlag = '0';
var _gaq = _gaq || []; document.observe('dom:loaded', function() {
_gaq.push(['_setAccount', 'UA-86235-1']);
_gaq.push(['_setDomainName', '.istockphoto.com']);
_gaq.push(['_setAllowLinker', true]);
_gaq.push(['_setAllowHash', false]);
_gaq.push(['_setVar', 'guest']);
_gaq.push(['_trackPageview']);

(function() {
var ga = document.createElement('script'); ga.type = 'text/javascript'; ga.async = true;
ga.src = ('https:' == document.location.protocol ? 'https://ssl' : 'http://www') + '.google-analytics.com/ga.js';
var g = document.getElementsByTagName('script')[0];
...[SNIP]...

Request 2

POST /signup HTTP/1.1
Host: secure.istockphoto.com
User-Agent: Mozilla/5.0 (Windows; U; Windows NT 6.1; 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
Connection: keep-alive
Cookie: iStockSession=2cc7699782db9292993592db651144e7; SSLB=B; __utma=1.648264806.1313846141.1313846141.1313846141.1; __utmb=1.4.10.1313846141; __utmc=1; __utmz=1.1313846141.1.1.utmcsr=fakereferrerdominator.com|utmccn=(referral)|utmcmd=referral|utmcct=/referrerPathName; __utmv=1.guest; s_cc=true; s_visit=1; ttc=1313846141931; gpv_07=iStock%7CMyAccount%7CSignUpStep1; undefined_s=First%20Visit; s_vnum=1314853200934%26vn%3D1; s_invisit=true; s_nr=1313846176999-New; s_sq=gettyistockphotoprod%3D%2526pid%253DiStock%25257CMyAccount%25257CSignUpStep1%2526pidt%253D1%2526oid%253DNext%252520Step%2526oidt%253D3%2526ot%253DSUBMIT; s_vi=[CS]v1|2727D9BA050125EE-60000108E02D8513[CE]
Content-Type: application/x-www-form-urlencoded
Content-Length: 611

signupFormtoken=YToxOntzOjU6InRva2VuIjtzOjMyOiI2MGIwYzgzYzFlMGU3OWMzNjk3Nzg3M2QyNDUwOWIyOSI7fQ%3D%3D&leftSide%5BloginInfo%5D%5Bemail%5D=&leftSide%5BloginInfo%5D%5BmemberName%5D=&leftSide%5BloginInfo%5
...[SNIP]...

Response 2

HTTP/1.1 200 OK
Server: Apache
X-Cnection: close
Content-Type: text/html; charset=utf-8
Vary: Accept-Encoding
Content-Length: 27324
Date: Sat, 20 Aug 2011 13:17:37 GMT
Connection: keep-alive
Cache-Control: no-store, no-cache, must-revalidate, post-check=0, pre-check=0
Expires: Thu, 19 Nov 1981 08:52:00 GMT
Pragma: no-cache

<!DOCTYPE html><html><head><meta charset="utf-8">
<meta name="keywords" content="stock photography, stock agency, photos, digital stock, royalty free" >
<meta name="description" content="Browse the be
...[SNIP]...

</script><script type="text/javascript">
//
</script>
<script type="text/javascript">
//<!--

var lpLanguage = 'english';
var lpUnit = 'istock';
var lpLoginFlag = '0';
var _gaq = _gaq || []; document.observe('dom:loaded', function() {
_gaq.push(['_setAccount', 'UA-86235-1']);
_gaq.push(['_setDomainName', '.istockphoto.com']);
_gaq.push(['_setAllowLinker', true]);
_gaq.push(['_setAllowHash', false]);
_gaq.push(['_setVar', 'guest']);
_gaq.push(['_trackPageview']);

(function() {
var ga = document.cre
...[SNIP]...

5. Cross-domain script include previous next

Summary

Severity:	Information
Confidence:	Certain
Host:	https://secure.istockphoto.com
Path:	/signup

Issue detail

The response dynamically includes the following scripts from other domains:

https://i.istockimg.com/static/1313700583/js/f5-bundle.js
https://i.istockimg.com/static/1313700583/js/form-bundle.js
https://i.istockimg.com/static/1313700583/js/password-meter.js
https://i.istockimg.com/static/1313700583/js/protoculous.js
https://i.istockimg.com/static/1313700583/js/quicksignup-bundle.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

Response

6. Robots.txt file previous next

Summary

Severity:	Information
Confidence:	Certain
Host:	https://secure.istockphoto.com
Path:	/signup

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: secure.istockphoto.com

Response

HTTP/1.0 200 OK
Server: Apache
Content-Length: 26
X-Cnection: close
Content-Type: text/plain
Date: Sat, 20 Aug 2011 13:16:21 GMT
Connection: close
Cache-Control: no-store, no-cache, must-revalidate, post-check=0, pre-check=0
Expires: Thu, 19 Nov 1981 08:52:00 GMT
Pragma: no-cache

User-agent: *
Disallow: /

7. SSL certificate previous

Summary

Severity:	Information
Confidence:	Certain
Host:	https://secure.istockphoto.com
Path:	/

Issue detail

The server presented a valid, trusted SSL certificate. This issue is purely informational.

The server presented the following certificates:

Server certificate

Issued to:	secure.istockphoto.com,ST=Alberta
Issued by:	Akamai Subordinate CA 3
Valid from:	Fri Jul 29 15:31:19 GMT-06:00 2011
Valid to:	Sun Jul 29 15:31:19 GMT-06:00 2012

Certificate chain #1

Issued to:	Akamai Subordinate CA 3
Issued by:	GTE CyberTrust Global Root
Valid from:	Thu May 11 09:32:00 GMT-06:00 2006
Valid to:	Sat May 11 17:59:00 GMT-06:00 2013

Certificate chain #2

Issued to:	GTE CyberTrust Global Root
Issued by:	GTE CyberTrust Global Root
Valid from:	Wed Aug 12 18:29:00 GMT-06:00 1998
Valid to:	Mon Aug 13 17:59:00 GMT-06:00 2018

Issue background

SSL helps to protect the confidentiality and integrity of information in transit between the browser and server, and to provide authentication of the server's identity. To serve this purpose, the server must present an SSL certificate which is valid for the server's hostname, is issued by a trusted authority and is valid for the current date. If any one of these requirements is not met, SSL connections to the server will not provide the full protection for which SSL is designed.

It should be noted that various attacks exist against SSL in general, and in the context of HTTPS web connections. It may be possible for a determined and suitably-positioned attacker to compromise SSL connections without user detection even when a valid SSL certificate is used.

Report generated by XSS.CX at Sat Aug 20 07:23:42 GMT-06:00 2011.