OpenBSD ELF ld.so(1) privilege escalation

openbsd-elf-privilege-escalation (30441) The risk level is classified as MediumMedium Risk

Description:

OpenBSD on ELF-based systems could allow a local attacker to gain elevated privileges, caused by a vulnerability in the ld.so(1) program image. A local attacker could exploit this vulnerability to obtain sensitive information or gain elevated privileges on the system.

Platforms Affected:

  • OpenBSD, OpenBSD 3.9
  • OpenBSD, OpenBSD 4.0

Remedy:

For OpenBSD 4.0:
Apply the patch for this vulnerability (005_ldso.patch), as listed in the OpenBSD 4.0 errata. See References.

For OpenBSD 3.9:
Apply the patch for this vulnerability (016_ldso.patch), as listed in the OpenBSD 3.9 errata. See References.

Consequences:

Gain Privileges

References:

  • OpenBSD 3.0 errata, 016: SECURITY FIX: November 19, 2006 at http://www.openbsd.org/errata39.html#ldso.
  • OpenBSD 4.0 errata, 005: SECURITY FIX: November 19, 2006 at http://www.openbsd.org/errata.html#ldso.
  • BID-21188: OpenBSD LD.SO Local Environment Variable Clearing Vulnerability
  • CVE-2006-6164: The _dl_unsetenv function in loader.c in the ELF ld.so in OpenBSD 3.9 and 4.0 does not properly remove duplicate environment variables, which allows local users to pass dangerous variables such as LD_PRELOAD to loading processes, which might be leveraged to gain privileges.
  • SA22993: OpenBSD ELF ld.so Environment Cleaning Vulnerability
  • SECTRACK ID: 1017253: OpenBSD `ld.so(1)` May Let Local Users Gain Elevated Privileges

Reported:

Nov 19, 2006

The information within this database may change without notice. Use of this information constitutes acceptance for use in an AS IS condition. There are NO warranties, implied or otherwise, with regard to this information or its use. Any use of this information is at the user's risk. In no event shall the author/distributor (Internet Security Systems X-Force) be held liable for any damages whatsoever arising out of or in connection with the use or spread of this information.

Copyright (c) 1994-2008 Internet Security Systems, Inc. All rights reserved worldwide.

For corrections or additions please email xforce@iss.net

Return to the main page