__________________________________________________________ The U.S. Department of Energy Computer Incident Advisory Capability ___ __ __ _ ___ / | /_\ / \___ __|__ / \ \___ __________________________________________________________ INFORMATION BULLETIN pam_ldap authentication bypass vulnerability [Vulnerability Note VU#778916] August 24, 2005 18:00 GMT Number P-290 [REVISED 25 AUG 2005] [REVISED 17 Oct 2005] ______________________________________________________________________________ PROBLEM: A vulnerability in pam_ldap may allow a remote attacker to bypass the authentication mechanism. PLATFORM: UNIX-based systems Red Hat Desktop (v. 4) Red Hat Enterprise Linux AS, ES, WS (v. 4) DAMAGE: A vulnerability in pam_ldap may allow a remote attacker to bypass the authentication mechanism. If a pam_ldap client attempts to authenticate against an LDAP server that omits the optional error value from the PasswordPolicyResponseValue, the authentication attempt will always succeed. SOLUTION: Upgrade to current version. ______________________________________________________________________________ VULNERABILITY The risk is HIGH. Allows a remote attacker to bypass the ASSESSMENT: authentication mechanism. ______________________________________________________________________________ LINKS: CIAC BULLETIN: http://www.ciac.org/ciac/bulletins/p-290.shtml ORIGINAL BULLETIN: http://www.kb.cert.org/vuls/id/778916 ADDITIONAL LINKS: Debian Security Advisory http://www.debian.org/security/2005/dsa-785 Red Hat RHSA-2005:767-8 https://rhn.redhat.com/errata/RHSA-2005-767.html US-CERT Vulnerability Note VU#680620 http://www.kb.cert.org/vuls/id/680620 CVE/CAN: http://www.cve.mitre.org/cgi-bin/cvename.cgi?name= CAN-2005-2641 ______________________________________________________________________________ REVISION HISTORY: 08/25/2005 - added link to DSA-785. 10/17/2005 - added a link to Red Hat RHSA-2005:767-8 for Red Hat Desktop (v. 4) and Red Hat Enterprise Linux AS, ES, WS (v. 4). [***** Start Vulnerability Note VU#778916 *****] Vulnerability Note VU#778916 pam_ldap authentication bypass vulnerability Overview An error in the pam_ldap password policy control may allow a remote attacker to gain access to a system. I. Description pam_ldap provides LDAP authentication services for UNIX-based systems. A vulnerability in pam_ldap may allow a remote attacker to bypass the authentication mechanism. If a pam_ldap client attempts to authenticate against an LDAP server that omits the optional error value from the PasswordPolicyResponseValue, the authentication attempt will always succeed. Note that this vulnerability affects all versions of pam_ldap since version pam_ldap-169. However, if the underlying LDAP client library does not support LDAP version 3 controls, then this vulnerability is not present. II. Impact An unauthenticated, remote attacker may be able to bypass the pam_ldap authentication mechanism and gain access to a system, possibly with elevated privileges. III. Solution Upgrade pam_ldap This vulnerability was corrected in pam_ldap-180. Systems Affected Vendor Status Date Updated Apple Computer, Inc. Unknown 19-Aug-2005 Computer Associates Unknown 19-Aug-2005 Conectiva Inc. Unknown 19-Aug-2005 Debian Linux Unknown 19-Aug-2005 Engarde Secure Linux Unknown 19-Aug-2005 Hewlett-Packard Company Unknown 19-Aug-2005 IBM Corporation Unknown 19-Aug-2005 IBM Corporation (zseries) Unknown 19-Aug-2005 IBM eServer Unknown 19-Aug-2005 Immunix Communications, Inc. Unknown 19-Aug-2005 Ingrian, Inc. Unknown 19-Aug-2005 Lotus Unknown 19-Aug-2005 Mandriva, Inc. Unknown 19-Aug-2005 Microsoft Corporation Unknown 19-Aug-2005 Mirapoint, Inc. Unknown 19-Aug-2005 MontaVista Software Unknown 19-Aug-2005 Netscape Communications Corporation Unknown 19-Aug-2005 Novell Unknown 19-Aug-2005 OctetString, Inc. Unknown 19-Aug-2005 OpenLDAP Unknown 19-Aug-2005 OpenWall Linux Unknown 19-Aug-2005 Oracle, Inc. Unknown 19-Aug-2005 padl Vulnerable 24-Aug-2005 QUALCOMM Incorporated Unknown 19-Aug-2005 Red Hat Software, Inc. Unknown 19-Aug-2005 Sequent Computer Systems, Inc. Unknown 19-Aug-2005 Sun Microsystems, Inc. Unknown 19-Aug-2005 SuSe Not Vulnerable 22-Aug-2005 The SCO Group (SCO Linux) Unknown 19-Aug-2005 The Teamware Group Unknown 19-Aug-2005 Turbolinux Unknown 19-Aug-2005 References http://www.padl.com/OSS/pam_ldap.html Credit This vulnerability was reported by Luke Howard of padl. This document was written by Jeff Gennari. Other Information Date Public Date First Published 08/24/2005 01:07:56 PM Date Last Updated 08/24/2005 CERT Advisory CVE Name CAN-2005-2641 Metric 8.15 Document Revision 47 [***** End Vulnerability Note VU#778916 *****] _______________________________________________________________________________ CIAC wishes to acknowledge the contributions of US Cert for the information contained in this bulletin. _______________________________________________________________________________ CIAC, the Computer Incident Advisory Capability, is the computer security incident response team for the U.S. Department of Energy (DOE) and the emergency backup response team for the National Institutes of Health (NIH). CIAC is located at the Lawrence Livermore National Laboratory in Livermore, California. CIAC is also a founding member of FIRST, the Forum of Incident Response and Security Teams, a global organization established to foster cooperation and coordination among computer security teams worldwide. CIAC services are available to DOE, DOE contractors, and the NIH. CIAC can be contacted at: Voice: +1 925-422-8193 (7x24) FAX: +1 925-423-8002 STU-III: +1 925-423-2604 E-mail: ciac@ciac.org Previous CIAC notices, anti-virus software, and other information are available from the CIAC Computer Security Archive. World Wide Web: http://www.ciac.org/ Anonymous FTP: ftp.ciac.org PLEASE NOTE: Many users outside of the DOE, ESnet, and NIH computing communities receive CIAC bulletins. If you are not part of these communities, please contact your agency's response team to report incidents. Your agency's team will coordinate with CIAC. The Forum of Incident Response and Security Teams (FIRST) is a world-wide organization. A list of FIRST member organizations and their constituencies can be obtained via WWW at http://www.first.org/. This document was prepared as an account of work sponsored by an agency of the United States Government. Neither the United States Government nor the University of California nor any of their employees, makes any warranty, express or implied, or assumes any legal liability or responsibility for the accuracy, completeness, or usefulness of any information, apparatus, product, or process disclosed, or represents that its use would not infringe privately owned rights. Reference herein to any specific commercial products, process, or service by trade name, trademark, manufacturer, or otherwise, does not necessarily constitute or imply its endorsement, recommendation or favoring by the United States Government or the University of California. The views and opinions of authors expressed herein do not necessarily state or reflect those of the United States Government or the University of California, and shall not be used for advertising or product endorsement purposes. LAST 10 CIAC BULLETINS ISSUED (Previous bulletins available from CIAC) P-280: Security Vulnerability in The "printd" Daemon P-281: Security Vulnerabilities in the Sun StorEdge Enterprise Backup Software P-282: PHP PEAR XML-RPC Server Package Vulnerability P-283: Cisco Intrusion Prevention System Vulnerable to Privilege Escalation P-284: SSL Certificate Validation Vulnerability in IDS Management Software P-285: netpbm security update P-286: vim security update P-287: elm security update P-288: Security Vulnerability in Solaris 10 "DHCP" Clients P-289: mysql -- insecure temporary file