PR08-21: Cross-site Request Forgery (CSRF) on Novell GroupWise WebAccess allows email theft and other attacks Vulnerability found: 3rd October 2008 Vendor contacted: 3rd October 2008 Advisory publicly released: 30th January 2009 Severity: Critical Credits: Adrian Pastor of ProCheckUp Ltd (www.procheckup.com). ProCheckUp thanks Novell for working with us in such a professional manner. Successfully tested on: Novell GroupWise WebAcess 7.0.3 Novell has confirmed the following versions to be affected by this vulnerability: GroupWise 6.5x GroupWise 7.0, 7.01, 7.02x, 7.03 GroupWise 8.0 (shipping 8.0 release only) CVE reference: CVE-2009-0272 Description: Novell WebAccess is vulnerable to CSRF. Any HTTP request can be successfully forged which means that any configuration settings can be changed on behalf of the victim user by tricking him to either: - visit a page - click on a link - view the content of an email (HTML body or attachment) Perhaps, the most interesting CSRF attack that can be carried out is installing a persistent backdoor which forwards received emails to the attacker. By forging the requests that adds a new forwarding rule, a copy of any email sent to the victim user will be sent to the attacker's inbox. All the attacker needs to do is email the victim with a malicious link and trick him to click on it. Alternatively, the CSRF attack can be triggered by simply viewing an email sent by the attacker. Consequences: Attackers can steal emails, deface email signatures, etc ... Proof of concept (PoC): _As kindly requested by Novell, ProCheckUp will delay publication of the PoC details to allow GroupWise customers time to apply the recommended security patches._ References: http://www.procheckup.com/vulnerability_manager http://www.novell.com/documentation/gw7/gw7_userweb/index.html?page=/doc umentation/gw7/gw7_userweb/data/using_rules.html http://en.wikipedia.org/wiki/Cross-site_request_forgery Fix: http://www.novell.com/support/search.do?usemicrosite=true&searchString=7 002319 Legal: Copyright 2009 ProCheckUp Ltd. All rights reserved. Permission is granted for copying and circulating this Bulletin to the Internet community for the purpose of alerting them to problems, if and only if the Bulletin is not changed or edited in any way, is attributed to ProCheckUp indicating this web page URL, and provided such reproduction and/or distribution is performed for non-commercial purposes. Any other use of this information is prohibited. ProCheckUp is not liable for any misuse of this information by any third party. ProCheckUp is not responsible for the content of external Internet sites.