__________________________________________________________ The U.S. Department of Energy Computer Incident Advisory Capability ___ __ __ _ ___ / | /_\ / \___ __|__ / \ \___ __________________________________________________________ INFORMATION BULLETIN Red Hat Updated pam_smb packages fix remote buffer overflow [Red Hat RHSA-2003:261-07] August 26, 2003 18:00 GMT Number N-137 [REVISED 27 Oct 2003] ______________________________________________________________________________ PROBLEM: The pam_smb module is a pluggable authentication module (PAM) used to authenticate users using an external Server Message Block (SMB) server. A buffer overflow vulnerability has been found that affects unpatched versions of pam_smb up to and including 1.1.6. PLATFORM: Red Hat Linux 7.2, 7.3, 8, 9 Red Hat Enterprise Linux products DAMAGE: If not updated, an attacker can exploit the pam_smb configured to authenticate a remotely accessible service and remotely execute arbitrary code. SOLUTION: Apply patches as stated in Red Hat's Notification. ______________________________________________________________________________ VULNERABILITY The risk is MEDIUM. This is a buffer overflow vunlerability ASSESSMENT: where a remote user could possibly execute arbitrary code. ______________________________________________________________________________ LINKS: CIAC BULLETIN: http://www.ciac.org/ciac/bulletins/n-137.shtml ORIGINAL BULLETIN: https://rhn.redhat.com/errata/RHSA-2003-261.html ADDITIONAL LINKS: https://rhn.redhat.com/errata/RHSA-2003-262.html ______________________________________________________________________________ REVISION HISTORY: 10-27-03 - Added additional link to Red Hat Advisory RHSA2003-262-07 for information on their patches for Red Hat Enterprise Linux products. [***** Start Red Hat RHSA-2003:261-07 *****] Updated pam_smb packages fix remote buffer overflow. Advisory: RHSA-2003:261-07 Last updated on: 2003-08-26 Affected Products: Red Hat Linux 7.2 Red Hat Linux 7.3 Red Hat Linux 8.0 Red Hat Linux 9 CVEs (cve.mitre.org): CAN-2003-0686 Security Advisory Details: Updated pam_smb packages are now available which fix a security vulnerability (buffer overflow). The pam_smb module is a pluggable authentication module (PAM) used to authenticate users using an external Server Message Block (SMB) server. A buffer overflow vulnerability has been found that affects unpatched versions of pam_smb up to and including 1.1.6. On systems that use pam_smb and are configured to authenticate a remotely accessible service, an attacker can exploit this bug and remotely execute arbitrary code. The Common Vulnerabilities and Exposures project (cve.mitre.org) has assigned the name CAN-2003-0686 to this issue. Red Hat Linux versions 7.2, 7.3, 8.0, and 9 ship with versions of pam_smb that are vulnerable to this issue, however pam_smb is not enabled by default. Users of pam_smb are advised to upgrade to these erratum packages, which contain a patch to version 1.1.6 to correct this issue. Red Hat would like to thank Dave Airlie of the Samba team for notifying us of this issue. Updated packages: Red Hat Linux 7.2 -------------------------------------------------------------------------------- SRPMS: pam_smb-1.1.6-9.7.src.rpm [ via FTP ] [ via HTTP ] fd60d4b954d24b50901f5d8034246619 i386: pam_smb-1.1.6-9.7.i386.rpm [ via FTP ] [ via HTTP ] 98f57da32415dec75f43bbe57165cc62 ia64: pam_smb-1.1.6-9.7.ia64.rpm [ via FTP ] [ via HTTP ] 5e0ecb7ec7e24de6efc32ad8f439d0ff Red Hat Linux 7.3 -------------------------------------------------------------------------------- SRPMS: pam_smb-1.1.6-9.7.src.rpm [ via FTP ] [ via HTTP ] fd60d4b954d24b50901f5d8034246619 i386: pam_smb-1.1.6-9.7.i386.rpm [ via FTP ] [ via HTTP ] 98f57da32415dec75f43bbe57165cc62 Red Hat Linux 8.0 -------------------------------------------------------------------------------- SRPMS: pam_smb-1.1.6-9.8.src.rpm [ via FTP ] [ via HTTP ] 2e399b4016dac855bc3e01056c23a244 i386: pam_smb-1.1.6-9.8.i386.rpm [ via FTP ] [ via HTTP ] 8cb3feb19dd74abfb582546235ee9718 Red Hat Linux 9 -------------------------------------------------------------------------------- SRPMS: pam_smb-1.1.6-9.9.src.rpm [ via FTP ] [ via HTTP ] 5e31c7774d44716e4bc14f5d11eb54db i386: pam_smb-1.1.6-9.9.i386.rpm [ via FTP ] [ via HTTP ] 11b99a275c316e57a3fdb68ab63c90f4 Solution Before applying this update, make sure all previously released errata relevant to your system have been applied. To update all RPMs for your particular architecture, run: rpm -Fvh [filenames] where [filenames] is a list of the RPMs you wish to upgrade. Only those RPMs which are currently installed will be updated. Those RPMs which are not installed but included in the list will not be updated. Note that you can also use wildcards (*.rpm) if your current directory *only* contains the desired RPMs. Please note that this update is also available via Red Hat Network. Many people find this an easier way to apply updates. To use Red Hat Network, launch the Red Hat Update Agent with the following command: up2date This will start an interactive process that will result in the appropriate RPMs being upgraded on your system. References: http://cve.mitre.org/cgi-bin/cvename.cgi?name=CAN-2003-0686 ------------------------------------------------------------------------------ The listed packages are GPG signed by Red Hat, Inc. for security. Our key is available at: http://www.redhat.com/solutions/security/news/publickey/#key You can verify each package and see who signed it with the following command: rpm --checksig -v filename If you only wish to verify that each package has not been corrupted or tampered with, examine only the md5sum with the following command: md5sum filename The Red Hat security contact is security@redhat.com. More contact details at http://www.redhat.com/solutions/security/news/contact.html [***** End Red Hat RHSA-2003:261-07 *****] _______________________________________________________________________________ CIAC wishes to acknowledge the contributions of Red Hat 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. 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