- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - Gentoo Linux Security Advisory GLSA 200410-31 - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - http://security.gentoo.org/ - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - Severity: Low Title: Archive::Zip: Virus detection evasion Date: October 29, 2004 Bugs: #68616 ID: 200410-31 - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - Synopsis ======== Email virus scanning software relying on Archive::Zip can be fooled into thinking a ZIP attachment is empty while it contains a virus, allowing detection evasion. Background ========== Archive::Zip is a Perl module containing functions to handle ZIP archives. Affected packages ================= ------------------------------------------------------------------- Package / Vulnerable / Unaffected ------------------------------------------------------------------- 1 dev-perl/Archive-Zip < 1.14 >= 1.14 Description =========== Archive::Zip can be used by email scanning software (like amavisd-new) to uncompress attachments before virus scanning. By modifying the uncompressed size of archived files in the global header of the ZIP file, it is possible to fool Archive::Zip into thinking some files inside the archive have zero length. Impact ====== An attacker could send a carefully crafted ZIP archive containing a virus file and evade detection on some email virus-scanning software relying on Archive::Zip for decompression. Workaround ========== There is no known workaround at this time. Resolution ========== All Archive::Zip users should upgrade to the latest version: # emerge --sync # emerge --ask --oneshot --verbose ">=dev-perl/Archive-Zip-1.14" References ========== [ 1 ] iDEFENSE Security Advisory 10.18.04 http://www.idefense.com/application/poi/display?id=153 [ 2 ] rt.cpan.org bug #8077 http://rt.cpan.org/NoAuth/Bug.html?id=8077 Availability ============ This GLSA and any updates to it are available for viewing at the Gentoo Security Website: http://security.gentoo.org/glsa/glsa-200410-31.xml Concerns? ========= Security is a primary focus of Gentoo Linux and ensuring the confidentiality and security of our users machines is of utmost importance to us. Any security concerns should be addressed to security@gentoo.org or alternatively, you may file a bug at http://bugs.gentoo.org. License ======= Copyright 2004 Gentoo Foundation, Inc; referenced text belongs to its owner(s). The contents of this document are licensed under the Creative Commons - Attribution / Share Alike license. http://creativecommons.org/licenses/by-sa/1.0