|Main Archive Page > Month Archives > full-disclosure-uk archives|
Rapid7 Advisory R7-0033
Apache HTTP Server mod_proxy_ftp Wildcard Characters Cross-Site Scripting
Discovered: July 25, 2008
Published: August 5, 2008
o Apache HTTP Server 2.2.9 (and earlier 2.2.x versions) o Apache HTTP Server 2.0.63 (and earlier 2.0.x versions)
o Apache HTTP Server 1.3.x (because mod_proxy_ftp doesn't support wildcard characters)
The mod_proxy_ftp module of the Apache HTTP Server is vulnerable to a cross-site scripting vulnerability when handling requests with wildcard characters (aka globbing characters).
3. Vendor status and information
Apache HTTP Server Project
The developers were notified of this vulnerability on July 28, 2008 via the private security mailing list firstname.lastname@example.org. They acknowledged it within 12 hours. On July 29, they assigned it a CVE ID. On August 5, the vulnerability was fixed in all SVN branches:
o Commit to main trunk:
http://svn.apache.org/viewvc?view=rev&revision=682868 o Commit to 2.2 branch:
http://svn.apache.org/viewvc?view=rev&revision=682870 o Commit to 2.0 branch:
Upgrade to Apache HTTP Server 2.2.10 or 2.0.64 (as of August 6, these have not been released yet), or apply the patch from SVN commit r682868.
5. Detailed analysis
When Apache HTTP Server is configured with proxy support ("ProxyRequests On" in the configuration file), and when mod_proxy_ftp is enabled to support FTP-over-HTTP, requests containing wildcard characters (asterisk, tilde, opening square bracket, etc) such as:
GET ftp://host/*<foo> HTTP/1.0
lead to cross-site scripting in the response returned by mod_proxy_ftp:
<h2>Directory of ftp://host/*<foo></h2>
To exploit this vulnerability, 'host' must be running an FTP server, and the last directory component of the path (the XSS payload) must be composed of at least 1 wildcard character and must not contain any forward slashes. In practice, this last requirement is not an obstacle at all to develop working exploits, example:
Discovered by Marc Bevand of Rapid7.
7. Contact Information
Phone: +1 (617) 247-1717
8. Disclaimer and Copyright
Rapid7, LLC is not responsible for the misuse of the information provided in our security advisories. These advisories are a service to the professional security community. There are NO WARRANTIES with regard to this information. Any application or distribution of this information constitutes acceptance AS IS, at the user's own risk. This information is subject to change without notice.
This advisory Copyright (C) 2008 Rapid7, LLC. Permission is hereby granted to redistribute this advisory, providing that no changes are made and that the copyright notices and disclaimers remain intact.