XSS, Reflected Cross Site Scripting, CWE-79, CAPEC-86, DORK, GHDB, verify.authorize.net

Hoyt LLC Research investigates and reports on security vulnerabilities embedded in Web Applications and Products used in wide-scale deployment.

Report generated by XSS.CX at Mon May 09 07:57:30 CDT 2011.

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

1. Cross-site scripting (reflected)

2. Cross-domain Referer leakage

3. Robots.txt file

4. Content type incorrectly stated

5. SSL certificate

1. Cross-site scripting (reflected) next

Summary

Severity:	High
Confidence:	Certain
Host:	https://verify.authorize.net
Path:	/anetseal/

Issue detail

The value of the rurl request parameter is copied into the value of an HTML tag attribute which is not encapsulated in any quotation marks. The payload e4830%20style%3dx%3aexpr/**/ession(alert(1))%20dfd967efe8f was submitted in the rurl parameter. This input was echoed as e4830 style=x:expr/**/ession(alert(1)) dfd967efe8f 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 a dynamically evaluated expression with a style attribute to introduce arbirary JavaScript into the document. Note that this technique is specific to Internet Explorer, and may not work on other browsers.

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 /anetseal/?pid=3de2b6f5-d068-4960-b93c-80b3d36d8ffe&rurl=https%3A//www.clone-systems.com/ecommerce/login.php%3Faction%3Dsend_password_emaile4830%20style%3dx%3aexpr/**/ession(alert(1))%20dfd967efe8f HTTP/1.1
Host: verify.authorize.net
Connection: keep-alive
User-Agent: Mozilla/5.0 (Windows NT 6.1; WOW64) AppleWebKit/534.24 (KHTML, like Gecko) Chrome/11.0.696.60 Safari/534.24
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: Sat, 07 May 2011 01:17:23 GMT
Server: Microsoft-IIS/6.0
P3P: CP="NOI NID NAV"
X-Powered-By: ASP.NET
X-AspNet-Version: 1.1.4322
Cache-Control: no-cache
Pragma: no-cache
Expires: -1
Content-Type: text/html; charset=utf-8
Content-Length: 5955

<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.0 Transitional//EN" >
<html>
<head>
<title>Authorize.Net Verified Merchant Seal</title>
<meta name="GENERATOR" Content="Microsoft Visual St
...[SNIP]...
<a href= https://www.clone-systems.com/ecommerce/login.php?action=send_password_emaile4830 style=x:expr/**/ession(alert(1)) dfd967efe8f >
...[SNIP]...

2. Cross-domain Referer leakage previous next

Summary

Severity:	Information
Confidence:	Certain
Host:	https://verify.authorize.net
Path:	/anetseal/

Issue detail

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

https://verify.authorize.net/anetseal/?pid=3de2b6f5-d068-4960-b93c-80b3d36d8ffe&rurl=https%3A//www.clone-systems.com/ecommerce/login.php%3Faction%3Dsend_password_email

The response contains the following link to another domain:

https://www.clone-systems.com/ecommerce/login.php?action=send_password_email

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.

Request

GET /anetseal/?pid=3de2b6f5-d068-4960-b93c-80b3d36d8ffe&rurl=https%3A//www.clone-systems.com/ecommerce/login.php%3Faction%3Dsend_password_email HTTP/1.1
Host: verify.authorize.net
Connection: keep-alive
User-Agent: Mozilla/5.0 (Windows NT 6.1; WOW64) AppleWebKit/534.24 (KHTML, like Gecko) Chrome/11.0.696.60 Safari/534.24
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: Sat, 07 May 2011 01:16:25 GMT
Server: Microsoft-IIS/6.0
P3P: CP="NOI NID NAV"
X-Powered-By: ASP.NET
X-AspNet-Version: 1.1.4322
Cache-Control: no-cache
Pragma: no-cache
Expires: -1
Content-Type: text/html; charset=utf-8
Content-Length: 5797

<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.0 Transitional//EN" >
<html>
<head>
<title>Authorize.Net Verified Merchant Seal</title>
<meta name="GENERATOR" Content="Microsoft Visual St
...[SNIP]...
<td class="MainHeaderFont">
<a href= https://www.clone-systems.com/ecommerce/login.php?action=send_password_email > www.clone-systems.com</a>
...[SNIP]...
<p>
You can be confident in knowing that <a href= https://www.clone-systems.com/ecommerce/login.php?action=send_password_email > www.clone-systems.com</a>
...[SNIP]...

3. Robots.txt file previous next

Summary

Severity:	Information
Confidence:	Certain
Host:	https://verify.authorize.net
Path:	/anetseal/

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: verify.authorize.net

Response

HTTP/1.1 200 OK
Content-Length: 28
Content-Type: text/plain
Last-Modified: Wed, 21 Feb 2007 20:25:16 GMT
Accept-Ranges: bytes
ETag: "09eb465f655c71:85f"
Server: Microsoft-IIS/6.0
P3P: CP="NOI NID NAV"
X-Powered-By: ASP.NET
Date: Sat, 07 May 2011 01:16:27 GMT
Connection: close

User-agent: *
Disallow: /

4. Content type incorrectly stated previous next

Summary

Severity:	Information
Confidence:	Firm
Host:	https://verify.authorize.net
Path:	/anetseal/images/secure90x72.gif

Issue detail

The response contains the following Content-type statement:

Content-Type: image/gif

The response states that it contains a GIF image. However, it actually appears to contain a PNG 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 /anetseal/images/secure90x72.gif HTTP/1.1
Host: verify.authorize.net
Connection: keep-alive
Referer: https://www.clone-systems.com/ecommerce/login.php?action=reset_password
User-Agent: Mozilla/5.0 (Windows NT 6.1; WOW64) AppleWebKit/534.24 (KHTML, like Gecko) Chrome/11.0.696.60 Safari/534.24
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
Content-Length: 2894
Content-Type: image/gif
Last-Modified: Fri, 26 Mar 2010 17:33:22 GMT
Accept-Ranges: bytes
ETag: "0dd746eacdca1:a13"
Server: Microsoft-IIS/6.0
P3P: CP="NOI NID NAV"
X-Powered-By: ASP.NET
Date: Sat, 07 May 2011 00:56:38 GMT

.PNG
.
...IHDR...Z...H.....v.......tEXtSoftware.Adobe ImageReadyq.e<..
.IDATx...?.+G...G.G...pK...ED.S..#DG..P..FQ:#.D.8....'BH....H.n...".E..... ..?.....w..]..{o.H#..g..3.<...;s...{O...S...zh...|g.
...[SNIP]...

5. SSL certificate previous

Summary

Severity:	Information
Confidence:	Certain
Host:	https://verify.authorize.net
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:	*.authorize.net
Issued by:	Entrust Certification Authority - L1C
Valid from:	Wed Mar 31 12:04:00 CDT 2010
Valid to:	Fri Mar 30 12:33:57 CDT 2012

Certificate chain #1

Issued to:	Entrust Certification Authority - L1C
Issued by:	Entrust.net Certification Authority (2048)
Valid from:	Thu Dec 10 14:43:54 CST 2009
Valid to:	Tue Dec 10 15:13:54 CST 2019

Certificate chain #2

Issued to:	Entrust.net Certification Authority (2048)
Issued by:	Entrust.net Certification Authority (2048)
Valid from:	Fri Dec 24 11:50:51 CST 1999
Valid to:	Tue Jul 24 09:15:12 CDT 2029

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 Mon May 09 07:57:30 CDT 2011.