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=/documentation/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=7002319



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