From koon@gentoo.org Tue Nov 29 12:55:55 2005 From: Thierry Carrez To: gentoo-announce@lists.gentoo.org Cc: full-disclosure@lists.grok.org.uk, bugtraq@securityfocus.com, security-alerts@linuxsecurity.com Date: Mon, 28 Nov 2005 11:18:47 +0100 Subject: [Full-disclosure] [ GLSA 200511-23 ] chmlib, KchmViewer: Stack-based buffer overflow - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - Gentoo Linux Security Advisory GLSA 200511-23 - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - http://security.gentoo.org/ - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - Severity: Normal Title: chmlib, KchmViewer: Stack-based buffer overflow Date: November 28, 2005 Bugs: #110557 ID: 200511-23 - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - Synopsis ======== chmlib and KchmViewer contain a buffer overflow vulnerability which may lead to the execution of arbitrary code. Background ========== chmlib is a library for dealing with Microsoft ITSS and CHM format files. KchmViewer is a CHM viewer that includes its own copy of the chmlib library. Affected packages ================= ------------------------------------------------------------------- Package / Vulnerable / Unaffected ------------------------------------------------------------------- 1 app-doc/chmlib < 0.37.4 >= 0.37.4 2 app-doc/kchmviewer < 1.1 >= 1.1 ------------------------------------------------------------------- 2 affected packages on all of their supported architectures. ------------------------------------------------------------------- Description =========== Sven Tantau reported about a buffer overflow vulnerability in chmlib. The function "_chm_decompress_block()" does not properly perform boundary checking, resulting in a stack-based buffer overflow. Impact ====== By convincing a user to open a specially crafted ITSS or CHM file, using KchmViewer or a program makes use of chmlib, a remote attacker could execute arbitrary code with the privileges of the user running the software. Workaround ========== There is no known workaround at this time. Resolution ========== All chmlib users should upgrade to the latest version: # emerge --sync # emerge --ask --oneshot --verbose ">=app-doc/chmlib-0.37.4" All KchmViewer users should upgrade to the latest version: # emerge --sync # emerge --ask --oneshot --verbose ">=app-doc/kchmviewer-1.1" References ========== [ 1 ] CVE-2005-3318 http://www.cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2005-3318 Availability ============ This GLSA and any updates to it are available for viewing at the Gentoo Security Website: http://security.gentoo.org/glsa/glsa-200511-23.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 2005 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/2.0 [ Part 1.2, "OpenPGP digital signature" Application/PGP-SIGNATURE ] [ 196bytes. ] [ Unable to print this part. ] [ Part 2: "Attached Text" ] _______________________________________________ Full-Disclosure - We believe in it. Charter: http://lists.grok.org.uk/full-disclosure-charter.html Hosted and sponsored by Secunia - http://secunia.com/