-----BEGIN PGP SIGNED MESSAGE----- CERT Advisory CA-2002-11 Heap Overflow in Cachefs Daemon (cachefsd) Original release date: May 06, 2002 Last revised: Source: CERT/CC A complete revision history can be found at the end of this file. Systems Affected * Sun Solaris 2.5.1, 2.6, 7, and 8 (SPARC and Intel Architectures) Overview Sun's NFS/RPC file system cachefs daemon (cachefsd) is shipped and installed by default with Sun Solaris 2.5.1, 2.6, 7, and 8 (SPARC and Intel architectures). A remotely exploitable vulnerability exists in cachefsd that could permit a remote attacker to execute arbitrary code with the privileges of the cachefsd, typically root. The CERT/CC has received credible reports of scanning and exploitation of Solaris systems running cachefsd. I. Description A remotely exploitable heap overflow exists in the cachefsd program shipped and installed by default with Sun Solaris 2.5.1, 2.6, 7, and 8 (SPARC and Intel architectures). Cachefsd caches requests for operations on remote file systems mounted via the use of NFS protocol. A remote attacker can send a crafted RPC request to the cachefsd program to exploit the vulnerability. Logs of exploitation attempts may resemble the following: May 16 22:46:08 victim-host inetd: /usr/lib/fs/cachefs/cachefsd: Segmentation Fault - core dumped May 16 22:46:21 victim-host last message repeated 7 times May 16 22:46:22 victim-host inetd: /usr/lib/fs/cachefs/cachefsd: Bus Error- core dumped May 16 22:46:24 victim-host inetd: /usr/lib/fs/cachefs/cachefsd: Segmentation Fault - core dumped May 16 22:46:56 victim-host inetd: /usr/lib/fs/cachefs/cachefsd: Bus Error - core dumped May 16 22:46:59 victim-host last message repeated 1 time May 16 22:47:02 victim-host inetd: /usr/lib/fs/cachefs/cachefsd: Segmentation Fault - core dumped May 16 22:47:07 victim-host last message repeated 3 times May 16 22:47:09 victim-host inetd: /usr/lib/fs/cachefs/cachefsd: Hangup May 16 22:47:11 victim-host inetd: /usr/lib/fs/cachefs/cachefsd: Segmentation Fault - core dumped According a Sun Alert Notification, failed attempts to exploit this vulnerability may leave a core dump file in the root directory. The presence of the core file does not preclude the success of subsequent attacks. Additionally, if the file /etc/cachefstab exists, it may contain unusual entries. This issue is also being referenced as CAN-2002-0085: http://cve.mitre.org/cgi-bin/cvename.cgi?name=CAN-2002-0085 The Australian Computer Emergency Response Team has also issued an advisory related to incident activity exploiting cachefsd: http://www.auscert.org.au/Information/Advisories/advisory/AA-2002.01.txt II. Impact A remote attacker may be able to execute code with the privileges of the cachefsd process, typically root. III. Solution Apply a patch from your vendor Appendix A contains information provided by vendors for this advisory. If a patch is not available, disable cachefsd in inetd.conf until a patch can be applied. If disabling the cachefsd is not an option, follow the suggested workaround in the Sun Alert Notification. Appendix A. - Vendor Information This appendix contains information provided by vendors for this advisory. As vendors report new information to the CERT/CC, we will update this section and note the changes in our revision history. If a particular vendor is not listed below, please check the Vulnerability Note (VU#635811) or contact your vendor directly. IBM IBM's AIX operating system, all versions, is not vulnerable. SGI SGI does not ship with SUN cachefsd, so IRIX is not vulnerable. Sun See the Sun Alert Notification available at http://sunsolve.sun.com/pub-cgi/retrieve.pl?doc=fsalert%2F44309. _________________________________________________________________ The CERT/CC acknowledges the eSecurity Online Team for discovering and reporting on this vulnerability and thanks Sun Microsystems for their technical assistance. _________________________________________________________________ Feedback can be directed to the authors: Jason A. Rafail and Jeffrey S. Havrilla ______________________________________________________________________ This document is available from: http://www.cert.org/advisories/CA-2002-11.html ______________________________________________________________________ CERT/CC Contact Information Email: firstname.lastname@example.org Phone: +1 412-268-7090 (24-hour hotline) Fax: +1 412-268-6989 Postal address: CERT Coordination Center Software Engineering Institute Carnegie Mellon University Pittsburgh PA 15213-3890 U.S.A. CERT/CC personnel answer the hotline 08:00-17:00 EST(GMT-5) / EDT(GMT-4) Monday through Friday; they are on call for emergencies during other hours, on U.S. holidays, and on weekends. Using encryption We strongly urge you to encrypt sensitive information sent by email. Our public PGP key is available from http://www.cert.org/CERT_PGP.key If you prefer to use DES, please call the CERT hotline for more information. Getting security information CERT publications and other security information are available from our web site http://www.cert.org/ To subscribe to the CERT mailing list for advisories and bulletins, send email to email@example.com. Please include in the body of your message subscribe cert-advisory * "CERT" and "CERT Coordination Center" are registered in the U.S. Patent and Trademark Office. ______________________________________________________________________ NO WARRANTY Any material furnished by Carnegie Mellon University and the Software Engineering Institute is furnished on an "as is" basis. Carnegie Mellon University makes no warranties of any kind, either expressed or implied as to any matter including, but not limited to, warranty of fitness for a particular purpose or merchantability, exclusivity or results obtained from use of the material. Carnegie Mellon University does not make any warranty of any kind with respect to freedom from patent, trademark, or copyright infringement. _________________________________________________________________ Conditions for use, disclaimers, and sponsorship information Copyright 2002 Carnegie Mellon University. Revision History May 06, 2002: Initial release -----BEGIN PGP SIGNATURE----- Version: PGP 6.5.8 iQCVAwUBPNbqwqCVPMXQI2HJAQHPBwP/ZElJx24KBdtWjqsaEv7qb9uFmA/5xOkc OgCZ/6EeXiEyK+D/faHAvttarxG5jABSrUnMjXI5aqa/3CaDmrMNnUKjYfxzt1GY TZFhLWUfE6F35sxRshLBwLmy88qkoZqLTqnWn/YqgCU+f8UUnqCIuVIxf2q1AgJj ExjXmDs3tbQ= =LUIX -----END PGP SIGNATURE-----
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