-----BEGIN PGP SIGNED MESSAGE----- Hash: SHA1 - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - Gentoo Linux Security Advisory GLSA 200711-29 - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - http://security.gentoo.org/ - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - Severity: High Title: Samba: Execution of arbitrary code Date: November 20, 2007 Bugs: #197519 ID: 200711-29 - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - Synopsis ======== Samba contains two buffer overflow vulnerabilities potentially resulting in the execution of arbitrary code, one of which is currently unfixed. Background ========== Samba is a suite of SMB and CIFS client/server programs for UNIX. Affected packages ================= ------------------------------------------------------------------- Package / Vulnerable / Unaffected ------------------------------------------------------------------- 1 net-fs/samba < 3.0.26a-r2 >= 3.0.26a-r2 Description =========== Two vulnerabilities have been reported in nmbd. Alin Rad Pop (Secunia Research) discovered a boundary checking error in the reply_netbios_packet() function which could lead to a stack-based buffer overflow (CVE-2007-5398). The Samba developers discovered a boundary error when processing GETDC logon requests also leading to a buffer overflow (CVE-2007-4572). Impact ====== To exploit the first vulnerability a remote unauthenticated attacker could send specially crafted WINS "Name Registration" requests followed by a WINS "Name Query" request. This might lead to execution of arbitrary code with elevated privileges. Note that this vulnerability is exploitable only when WINS server support is enabled in Samba. The second vulnerability could be exploited by sending specially crafted "GETDC" mailslot requests, but requires Samba to be configured as a Primary or Backup Domain Controller. It is not believed the be exploitable to execute arbitrary code. Workaround ========== To work around the first vulnerability, disable WINS support in Samba by setting "wins support = no" in the "global" section of your smb.conf and restart Samba. Resolution ========== The Samba 3.0.27 ebuild that resolves both vulnerabilities is currently masked due to a regression in the patch for the second vulnerability. Since no working patch exists yet, all Samba users should upgrade to 3.0.26a-r2, which contains a fix for the first vulnerability (CVE-2007-5398): # emerge --sync # emerge --ask --oneshot --verbose ">=net-fs/samba-3.0.26a-r2" An update to this temporary GLSA will be sent when the second vulnerability will be fixed. References ========== [ 1 ] CVE-2007-4572 http://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2007-4572 [ 2 ] CVE-2007-5398 http://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2007-5398 Availability ============ This GLSA and any updates to it are available for viewing at the Gentoo Security Website: http://security.gentoo.org/glsa/glsa-200711-29.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 2007 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/2.5 -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.4.7 (GNU/Linux) Comment: Using GnuPG with Mozilla - http://enigmail.mozdev.org iD8DBQFHQ1C2uhJ+ozIKI5gRAnDrAJ9rbv6PXnbEEz8jvaraJkfH814GEACeN6dk LTWtGdO+1xJLDW/uKaRwQGo= =ic/h -----END PGP SIGNATURE-----