From koon@gentoo.org Sat Dec 4 02:21:47 2004 From: Thierry Carrez To: gentoo-announce@lists.gentoo.org Cc: bugtraq@securityfocus.com, full-disclosure@lists.netsys.com, security-alerts@linuxsecurity.com Date: Fri, 03 Dec 2004 17:47:18 +0100 Subject: [ GLSA 200412-01 ] rssh, scponly: Unrestricted command execution - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - Gentoo Linux Security Advisory GLSA 200412-01 - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - http://security.gentoo.org/ - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - Severity: Normal Title: rssh, scponly: Unrestricted command execution Date: December 03, 2004 Bugs: #72815, #72816 ID: 200412-01 - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - Synopsis ======== rssh and scponly do not filter command-line options that can be exploited to execute any command, thereby allowing a remote user to completely bypass the restricted shell. Background ========== rssh and scponly are two restricted shells, allowing only a few predefined commands. They are often used as a complement to OpenSSH to provide access to remote users without providing any remote execution privileges. Affected packages ================= ------------------------------------------------------------------- Package / Vulnerable / Unaffected ------------------------------------------------------------------- 1 net-misc/scponly < 4.0 >= 4.0 2 app-shells/rssh <= 2.2.2 Vulnerable! ------------------------------------------------------------------- NOTE: Certain packages are still vulnerable. Users should migrate to another package if one is available or wait for the existing packages to be marked stable by their architecture maintainers. ------------------------------------------------------------------- 2 affected packages on all of their supported architectures. ------------------------------------------------------------------- Description =========== Jason Wies discovered that when receiving an authorized command from an authorized user, rssh and scponly do not filter command-line options that can be used to execute any command on the target host. Impact ====== Using a malicious command, it is possible for a remote authenticated user to execute any command (or upload and execute any file) on the target machine with user rights, effectively bypassing any restriction of scponly or rssh. Workaround ========== There is no known workaround at this time. Resolution ========== All scponly users should upgrade to the latest version: # emerge --sync # emerge --ask --oneshot --verbose ">=net-misc/scponly-4.0" Currently, there is no released version of rssh that contains a fix for these issues. The author declared that he cannot provide a fixed version at this time. Therefore, the rssh package has been hard-masked prior to complete removal from Portage, and current users are advised to unmerge the package. References ========== [ 1 ] BugTraq Posting http://www.securityfocus.com/archive/1/383046/2004-11-30/2004-12-06/0 Availability ============ This GLSA and any updates to it are available for viewing at the Gentoo Security Website: http://security.gentoo.org/glsa/glsa-200412-01.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/2.0 [ Part 2, "OpenPGP digital signature" Application/PGP-SIGNATURE ] [ 196bytes. ] [ Unable to print this part. ]