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Gentoo Linux Security Advisory GLSA 200611-06 |
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http://security.gentoo.org/ |
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Severity: Normal |
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Title: OpenSSH: Multiple Denial of Service vulnerabilities |
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Date: November 13, 2006 |
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Bugs: #149502 |
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ID: 200611-06 |
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Synopsis |
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======== |
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|
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Several Denial of Service vulnerabilities have been identified in |
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OpenSSH. |
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Background |
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========== |
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|
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OpenSSH is a complete SSH protocol version 1.3, 1.5 and 2.0 |
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implementation and includes sftp client and server support. |
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|
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Affected packages |
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================= |
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|
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------------------------------------------------------------------- |
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Package / Vulnerable / Unaffected |
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------------------------------------------------------------------- |
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1 net-misc/openssh < 4.4_p1-r5 >= 4.4_p1-r5 |
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Description |
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=========== |
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|
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Tavis Ormandy of the Google Security Team has discovered a |
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pre-authentication vulnerability, causing sshd to spin until the login |
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grace time has been expired. Mark Dowd found an unsafe signal handler |
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that was vulnerable to a race condition. It has also been discovered |
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that when GSSAPI authentication is enabled, GSSAPI will in certain |
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cases incorrectly abort. |
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Impact |
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====== |
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|
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The pre-authentication and signal handler vulnerabilities can cause a |
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Denial of Service in OpenSSH. The vulnerability in the GSSAPI |
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authentication abort could be used to determine the validity of |
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usernames on some platforms. |
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Workaround |
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========== |
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There is no known workaround at this time. |
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Resolution |
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========== |
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All OpenSSH users should upgrade to the latest version: |
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# emerge --sync |
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# emerge --ask --oneshot --verbose ">=net-misc/openssh-4.4_p1-r5" |
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References |
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========== |
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[ 1 ] CVE-2006-5051 |
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http://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2006-5051 |
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[ 2 ] CVE-2006-5052 |
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http://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2006-5052 |
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[ 3 ] OpenSSH Security Advisory |
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http://www.openssh.com/txt/release-4.4 |
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Availability |
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============ |
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This GLSA and any updates to it are available for viewing at |
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the Gentoo Security Website: |
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http://security.gentoo.org/glsa/glsa-200611-06.xml |
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Concerns? |
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========= |
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Security is a primary focus of Gentoo Linux and ensuring the |
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confidentiality and security of our users machines is of utmost |
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importance to us. Any security concerns should be addressed to |
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security@g.o or alternatively, you may file a bug at |
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http://bugs.gentoo.org. |
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License |
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======= |
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Copyright 2006 Gentoo Foundation, Inc; referenced text |
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belongs to its owner(s). |
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The contents of this document are licensed under the |
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Creative Commons - Attribution / Share Alike license. |
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http://creativecommons.org/licenses/by-sa/2.5 |
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