Penetration Testing mailing list archives
Re: http TRACE option
From: Chris McNab <chris.mcnab () trustmatta com>
Date: Fri, 18 Jan 2008 18:52:14 +0000
Hi,Here's the HTTP TRACE discussion from the 2nd edition of my book (http://www.oreilly.com/catalog/9780596510305/)
-- 8< -- snip -- 8< -- snip -- 8< -- snip -- 8< -- TRACE vulnerabilitiesIf the TRACE method is supported and the web server is running a poorly written application that is vulnerable to cross-site scripting (XSS), a cross-site tracing (XST) attack can be launched to compromise user cookie and session information. If the web server is running a static site with no server-side application or processing of user data, the impact of TRACE support is significantly reduced.
Enhancements to the security of web browsers and clients (such as Internet Explorer 6 SP1 and later) mean that standard XSS attacks are no longer widely effective. XST is an attack class developed by Jeremiah Grossman in 2003 that allows authentication details presented in HTTP headers (including cookies and base64-encoded authentication strings) to be compromised using a combination of XSS, client-side weaknesses, and support for the HTTP TRACE method server-side. Grossman developed the attack class in response to the enhanced security mechanisms introduced by Microsoft in Internet Explorer 6 SP1, which meant that the effectiveness of XSS was significantly reduced.
Papers discussing XST can be found at the following locations: http://www.cgisecurity.com/whitehat-mirror/WH-WhitePaper_XST_ebook.pdf http://www.securiteam.com/securityreviews/5YP0L1FHFC.html http://en.wikipedia.org/wiki/Cross-site_tracing XST depends on the following to launch an effective remote attack:Domain restriction bypass; The ability for a client-side script to bypass browser security policy settings and send data to web sites outside the domain that is being accessed
HTTP request-enabling technologies; Support for scripting languages client-side that can establish outbound HTTP connections (to push the stolen authentication credentials to a given location)
TRACE method support; The target web server that supports the TRACE methodUpon finding and seeding an XSS bug within the target web site, we call scripting languages client-side that perform a TRACE to the web server, and then push the output to our malicious server.
Good background information relating to basic XSS attacks can be found at the following locations:
http://www.spidynamics.com/whitepapers/SPIcross-sitescripting.pdf http://www.owasp.org/index.php/Cross_Site_Scripting http://www.cert.org/archive/pdf/cross_site_scripting.pdf http://en.wikipedia.org/wiki/Cross-site_scripting -- 8< -- snip -- 8< -- snip -- 8< -- snip -- 8< -- Hope that helps, Chris pentestr wrote:
Hi,what is the issue if TRACE option is enabled in web servers ? Nessus results always display it as warning.any idea... Thanks in advance. Rgds. P.T.
-- Chris McNab Technical Director Matta Consulting Limited Falstaff House 34 Bardolph Road Richmond upon Thames TW9 2LH T: 08700 77 11 00 W: www.trustmatta.comThe information contained in this email is intended only for the person(s) to whom it is addressed and may contain confidential or privileged material or information that is exempt from disclosure under applicable law. Information and attachments may be used only for the purpose for which they are sent, and copying, disclosure or distribution of any information contained herein is strictly prohibited.
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Current thread:
- http TRACE option pentestr (Jan 18)
- Re: http TRACE option jeffrey rivero (Jan 22)
- Re: http TRACE option Tim (Jan 22)
- Re: http TRACE option Florencio Cano (Jan 22)
- Re: http TRACE option Campbell Murray (Jan 22)
- Re: http TRACE option Chris McNab (Jan 22)
- RE: http TRACE option Maxime Ducharme (Jan 22)
- Re: http TRACE option Gleb Paharenko (Jan 22)
- Re: http TRACE option Alexander Bondarenko (Jan 22)
- Re: http TRACE option José M. Palazón Romero (Jan 22)
- Re: http TRACE option rajat swarup (Jan 22)
- RE: http TRACE option benoni.martin (Jan 22)
- Re: http TRACE option Bipin Upadhyay (Jan 22)
- Re: http TRACE option Trancer (Jan 22)