From koon@gentoo.org Fri May 14 17:53:44 2004 From: Thierry Carrez To: gentoo-announce@gentoo.org Cc: bugtraq@securityfocus.com, full-disclosure@lists.netsys.com, security-alerts@linuxsecurity.com Date: Fri, 14 May 2004 21:29:55 +0200 Subject: [Full-Disclosure] [ GLSA 200405-07 ] Exim verify=header_syntax buffer overflow -----BEGIN PGP SIGNED MESSAGE----- Hash: SHA1 - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - Gentoo Linux Security Advisory GLSA 200405-07 - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - http://security.gentoo.org/ - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - Severity: High Title: Exim verify=header_syntax buffer overflow Date: May 14, 2004 Bugs: #50217 ID: 200405-07 - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - Synopsis ======== When the verify=header_syntax option is set, there is a buffer overflow in Exim that allows remote execution of arbitrary code. Background ========== Exim is an highly configurable message transfer agent (MTA) developed at the University of Cambridge. Affected packages ================= ------------------------------------------------------------------- Package / Vulnerable / Unaffected ------------------------------------------------------------------- 1 net-mail/exim <= 4.33 >= 4.33-r1 Description =========== When the option "verify = header_syntax" is used in an ACL in the configuration file, Exim is vulnerable to a buffer overflow attack that can be triggered remotely by sending malicious headers in an email message. Note that this option is not enabled in Exim's default configuration file. Impact ====== This vulnerability can be exploited to trigger a denial of service attack and potentially execute arbitrary code with the rights of the user used by the Exim daemon (by default this is the "mail" user in Gentoo Linux). Workaround ========== Make sure the verify=header_syntax option is not used in your exim.conf file. Resolution ========== All users of Exim should upgrade to the latest stable version: # emerge sync # emerge -pv ">=net-mail/exim-4.33-r1" # emerge ">=net-mail/exim-4.33-r1" References ========== [ 1 ] CAN-2004-0400 http://cve.mitre.org/cgi-bin/cvename.cgi?name=CAN-2004-0400 Availability ============ This GLSA and any updates to it are available for viewing at the Gentoo Security Website: http://security.gentoo.org/glsa/glsa-200405-07.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 Technologies, 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 -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.2.4 (GNU/Linux) Comment: Using GnuPG with Mozilla - http://enigmail.mozdev.org iD8DBQFApR4zvcL1obalX08RAj4qAKCImDLrj24oLDw0LWp9GjS3dxeHpQCglZvQ fQIUyrGQF9T14nRKUWCceS4= =T3cu -----END PGP SIGNATURE----- _______________________________________________ Full-Disclosure - We believe in it. Charter: http://lists.netsys.com/full-disclosure-charter.html