CVE-2006-5051: Race Condition

Published Sep 27, 2006
·
Updated

OpenSSH 4.4 was released and mentions:

Fix an unsafe signal hander reported by Mark Dowd. The signal handler was vulnerable to a race condition that could be exploited to perform a pre-authentication denial of service. On portable OpenSSH, this vulnerability could theoretically lead to pre-authentication remote code execution if GSSAPI authentication is enabled, but the likelihood of successful exploitation appears remote.

This could only affect RHEL4 as previous RHEL did not support GSSAPI

Other sources

Signal handler race condition in OpenSSH before 4.4 allows remote attackers to cause a denial of service (crash), and possibly execute arbitrary code if GSSAPI authentication is enabled, via unspecified vectors that lead to a double-free.

MITRE

Affected Software

61 affected componentsFixes available
redhat/RHSA-2006<0697
0697
OpenBSD OpenSSH=3.8
OpenBSD OpenSSH=3.8.1p1
OpenBSD OpenSSH=3.2.2
OpenBSD OpenSSH=3.1
OpenBSD OpenSSH=3.0.2p1
OpenBSD OpenSSH=3.8.1
OpenBSD OpenSSH=2.1.1
OpenBSD OpenSSH=3.7.1p2
OpenBSD OpenSSH=3.2.3p1
OpenBSD OpenSSH=3.1p1
OpenBSD OpenSSH=2.5.1
OpenBSD OpenSSH=2.9.9p2
OpenBSD OpenSSH=3.6.1p2
OpenBSD OpenSSH=3.9
OpenBSD OpenSSH=3.0
OpenBSD OpenSSH=1.2.1
OpenBSD OpenSSH=2.2
OpenBSD OpenSSH=3.2
OpenBSD OpenSSH=3.6
OpenBSD OpenSSH=1.2.3
OpenBSD OpenSSH=3.7
OpenBSD OpenSSH=4.0p1
OpenBSD OpenSSH=3.5p1
OpenBSD OpenSSH=3.0.1p1
OpenBSD OpenSSH=3.7.1p1
OpenBSD OpenSSH=2.1
OpenBSD OpenSSH=1.2
OpenBSD OpenSSH=3.3
OpenBSD OpenSSH=3.2.2p1
OpenBSD OpenSSH=3.9.1p1
OpenBSD OpenSSH=3.0.2
OpenBSD OpenSSH=3.4p1
OpenBSD OpenSSH=3.6.1p1
OpenBSD OpenSSH=3.0.1
OpenBSD OpenSSH=2.9.9
OpenBSD OpenSSH=3.6.1
OpenBSD OpenSSH=4.1p1
OpenBSD OpenSSH=1.2.2
OpenBSD OpenSSH=4.2p1
OpenBSD OpenSSH=2.9p1
OpenBSD OpenSSH=2.9
OpenBSD OpenSSH=3.7.1
OpenBSD OpenSSH=1.2.27
OpenBSD OpenSSH=4.2
OpenBSD OpenSSH=2.5.2
OpenBSD OpenSSH=2.3
OpenBSD OpenSSH=3.4
OpenBSD OpenSSH=4.3p1
OpenBSD OpenSSH=3.5
OpenBSD OpenSSH=2.5
OpenBSD OpenSSH=3.0p1
OpenBSD OpenSSH=3.3p1
OpenBSD OpenSSH=4.3
OpenBSD OpenSSH=4.0
OpenBSD OpenSSH=3.9.1
OpenBSD OpenSSH=2.9p2
OpenBSD OpenSSH<=4.4
Debian Debian Linux=3.1
Apple Mac OS X Server<10.3.9
Apple Mac OS X Server>=10.4<=10.4.8

Event History

Sep 27, 2006
CVE Published
via MITRE·11:00 PM
Data Sourced
via MITRE·11:00 PM
Description
Data Sourced
via NVD·11:07 PM
DescriptionSeverityWeaknessAffected Software
Jul 1, 2024
News Published
via BleepingComputer·01:37 PM
News Published
via BleepingComputer·01:38 PM
News Published
via The Register·02:01 PM
News Published
via The Register·02:05 PM
Jul 2, 2024
News Published
via ZDNet·01:02 PM
Jul 6, 2024
News Published
via ZDNet·02:24 PM
Apr 24, 2025
Known Exploited
07:55 PM

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Frequently Asked Questions

1

What is the severity of CVE-2006-5051?

CVE-2006-5051 is classified as a medium severity vulnerability due to its potential for a pre-authentication denial of service.

2

How do I fix CVE-2006-5051?

To mitigate CVE-2006-5051, update OpenSSH to a version beyond 4.4, which contains the necessary patches.

3

What versions of OpenSSH are affected by CVE-2006-5051?

Affected versions include OpenSSH 4.4 and earlier, along with various earlier versions from the 3.x series and below.

4

Can CVE-2006-5051 lead to an actual exploit?

Yes, it can be exploited to create a denial of service condition, affecting the availability of the affected systems.

5

Is CVE-2006-5051 specific to any operating system?

CVE-2006-5051 impacts multiple operating systems that use vulnerable versions of OpenSSH, including Red Hat, Debian, and macOS.

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