unarj file name buffer overflow

unarj-longfilename-bo (18044) The risk level is classified as HighHigh Risk


unarj is vulnerable to a buffer overflow, caused by improper bounds checking of user-supplied input. By sending a specially-crafted long file name, a remote attacker could overflow a buffer and execute arbitrary code on the system or cause the system to crash, once processed by unarj.


Gain Access


For Gentoo Linux:
Upgrade to the latest version of unarj (2.63a-r2 or later), as listed in GLSA 200411-29. See References.

For SUSE Linux:
Apply the appropriate fixed packages via the SUSE FTP server or the YaST Online Update, as listed in SUSE Security Summary Report SUSE-SR:2004:003. See References.

For Debian GNU/Linux 3.0(woody):
Upgrade to the latest version of unarj (2.43-3woody1 or later), as listed in DSA-652-1. See References.

For Red Hat Linux:
Refer to RHSA-2005:007-05 for patch, upgrade, or suggested workaround information. See References.

For other distributions:
Contact your vendor for upgrade or patch information.


  • ARJ Software Web site: ARJ Software.
  • BID-11665: ARJ Software UNARJ Remote Buffer Overflow Vulnerability
  • CVE-2004-0947: Buffer overflow in unarj before 2.63a-r2 allows remote attackers to execute arbitrary code via an arj archive that contains long filenames.
  • DSA-652: unarj -- several vulnerabilities
  • GLSA-200411-29: unarj: Long filenames buffer overflow and a path traversal vulnerability
  • RHSA-2005-007: unarj security update
  • SUSE-SR:2004:003: SUSE Security Summary Report

Platforms Affected:

  • Debian Debian Linux 3.0
  • Gentoo Linux
  • Microsoft Windows 95
  • Microsoft Windows 98
  • RedHat Enterprise Linux 2.1 AS
  • RedHat Enterprise Linux 2.1 WS
  • RedHat Enterprise Linux 2.1 ES
  • RedHat Linux Advanced Workstation 2.1 Itanium
  • Robert K Jung unarj 2.43-3
  • Robert K Jung unarj 2.63a
  • SUSE SuSE Linux


Nov 11, 2004

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 (IBM 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.

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