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Home >> Browse Vulnerability Assessment Database >> Gentoo Local Security Checks >> [GLSA-200611-06] OpenSSH: Multiple Denial of Service vulnerabilities

Vulnerability Assessment Details

[GLSA-200611-06] OpenSSH: Multiple Denial of Service vulnerabilities

Vulnerability Assessment Summary
OpenSSH: Multiple Denial of Service vulnerabilities

Detailed Explanation for this Vulnerability Assessment
The remote host is affected by the vulnerability described in GLSA-200611-06
(OpenSSH: Multiple Denial of Service vulnerabilities)

Tavis Ormandy of the Google Security Team has discovered a
pre-authentication vulnerability, causing sshd to spin until the login
grace time has been expired. Mark Dowd found an unsafe signal handler
that was vulnerable to a race condition. It has also been discovered
that when GSSAPI authentication is enabled, GSSAPI will in certain
cases incorrectly abort.

Impact

The pre-authentication and signal handler vulnerabilities can cause a
Denial of Service in OpenSSH. The vulnerability in the GSSAPI
authentication abort could be used to acertain the validity of
usernames on some platforms.

Workaround

There is no known workaround at this time.

References:
http://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2006-5051
http://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2006-5052
http://www.openssh.com/txt/release-4.4

Solution:
All OpenSSH users should upgrade to the latest version:
# emerge --sync
# emerge --ask --oneshot --verbose ">=net-misc/openssh-4.4_p1-r5"

Network Security Threat Level: Medium

Networks Security ID:

Vulnerability Assessment Copyright: (C) 2006 Michel Arboi

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