-----BEGIN PGP SIGNED MESSAGE----- Hash: SHA1 iDefense Security Advisory 04.15.09 http://labs.idefense.com/intelligence/vulnerabilities/ Apr 15, 2009 I. BACKGROUND IBM's AIX is a Unix operating system based on System V, which runs on the PowerPC (PPC) architecture. For more information, visit the product web site at the following URL. http://www.ibm.com/systems/power/software/aix/index.html II. DESCRIPTION Local exploitation of a buffer overflow vulnerability in IBM Corp.'s Advanced Interactive eXecutive (AIX) could allow an attacker to gain root privileges. The set-uid root binary "muxatmd" concatenates the calling program name with the static string ".pid". The destination buffer passed to the function call used for concatenation is a static-sized stack buffer. Since no bounds checking is performed, a stack-based buffer overflow can occur when a long program name is given. III. ANALYSIS Exploitation of this issue allows an attacker to execute arbitrary code as root. An attacker would need to construct a malicious application that runs the "muxatmd" program with a malformed parameter. IV. DETECTION iDefense has confirmed the existence of this vulnerability in IBM Corp.'s AIX version 5.3 (5300-09-02-0849). Other versions may also be affected. V. WORKAROUND Removing the set-uid bit from the "/usr/sbin/muxatmd" binary will provide a workaround for this issue. However, this will make the program unusable for non-root users. VI. VENDOR RESPONSE IBM has released a patch which addresses this issue. For more information, consult their advisory at the following URL: http://aix.software.ibm.com/aix/efixes/security/muxatmd_advisory.asc VII. CVE INFORMATION A Mitre Corp. Common Vulnerabilities and Exposures (CVE) number has not been assigned yet. VIII. DISCLOSURE TIMELINE 12/16/2008 - Initial Vendor Notification 12/16/2008 - Requested PoC 01/06/2009 - PoC Sent 04/15/2009 - Coordinated Public Disclosure IX. CREDIT The discoverer of this vulnerability wishes to remain anonymous. Get paid for vulnerability research http://labs.idefense.com/methodology/vulnerability/vcp.php Free tools, research and upcoming events http://labs.idefense.com/ X. LEGAL NOTICES Copyright © 2009 iDefense, Inc. Permission is granted for the redistribution of this alert electronically. It may not be edited in any way without the express written consent of iDefense. If you wish to reprint the whole or any part of this alert in any other medium other than electronically, please e-mail customerservice@idefense.com for permission. Disclaimer: The information in the advisory is believed to be accurate at the time of publishing based on currently available information. Use of the information constitutes acceptance for use in an AS IS condition. There are no warranties with regard to this information. Neither the author nor the publisher accepts any liability for any direct, indirect, or consequential loss or damage arising from use of, or reliance on, this information. -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.4.7 (MingW32) Comment: Using GnuPG with Mozilla - http://enigmail.mozdev.org iD8DBQFJ5j9rbjs6HoxIfBkRAqlGAJ4zjUILVWagJjoTJZv8clxzK9VwSQCgwNrX y6d63LqSnVisMgB2DlxHPDY= =Oct9 -----END PGP SIGNATURE----- _______________________________________________ Full-Disclosure - We believe in it. Charter: http://lists.grok.org.uk/full-disclosure-charter.html Hosted and sponsored by Secunia - http://secunia.com/