OpenSSH wildcard security bypass

openssh-cve20142532-sec-bypass (91986) The risk level is classified as MediumMedium Risk

Description:

OpenSSH could allow a remote attacker to bypass security restrictions, caused by the inclusion of wildcard characters in the AcceptEnv lines of the sshd_config configuration file within the sshd program. By using a substring before a wildcard character, an attacker could exploit this vulnerability to bypass intended environment restrictions.

*CVSS:

Base Score: 5
  Access Vector: Network
  Access Complexity: Low
  Authentication: None
  Confidentiality Impact: None
  Integrity Impact: Partial
  Availability Impact: None
 
Temporal Score: 3.7
  Exploitability: Unproven
  Remediation Level: Official-Fix
  Report Confidence: Confirmed

Consequences:

Bypass Security

Remedy:

Upgrade to the latest version of OpenSSH (6.6 or later), available from the OpenSSH Web site. See References.

References:

  • OpenSSH Web Site: Changes since OpenSSH 6.6.
  • BID-66355: OpenSSH 'child_set_env()' Function Security Bypass Vulnerability
  • CVE-2014-2532: sshd in OpenSSH before 6.6 does not properly support wildcards on AcceptEnv lines in sshd_config, which allows remote attackers to bypass intended environment restrictions by using a substring located before a wildcard character.
  • RHSA-2014-1552: Moderate: openssh security, bug fix, and enhancement update
  • SA57488: OpenSSH "child_set_env()" Security Bypass Security Issue

Platforms Affected:

  • OpenBSD OpenSSH 6.5
  • RedHat Enterprise Linux 6 Server
  • RedHat Enterprise Linux 6 Workstation
  • RedHat Enterprise Linux Desktop 6
  • RedHat Enterprise Linux HPC Node 6

Reported:

Mar 21, 2014

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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 IBM 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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