OpenSSH sshd.c LoginGraceTime denial of service
| openssh-sshdc-logingracetime-dos (20930) |  Low Risk |
Description:
OpenSSH is vulnerable to a denial of service caused by a vulnerability in the LoginGraceTime. A local attacker could open multiple SSH clients without logging in to cause other connection attempts to fail to establish connections.
Platforms Affected:
- OpenBSD, OpenSSH 3.6.1p2
- OpenBSD, OpenSSH 3.7.1p2
- RedHat, Enterprise Linux 3 Desktop
- RedHat, Enterprise Linux 3 AS
- RedHat, Enterprise Linux 3 ES
- RedHat, Enterprise Linux 3 WS
- VMware, ESX Server 2.0.2
- VMware, ESX Server 2.1.3
- VMware, ESX Server 2.5.3
Remedy:
For Red Hat Linux:
Refer to RHSA-2005:550-6 for patch, upgrade, or suggested workaround information. See References.
For VMware ESX Server 2.0.2:
Apply the patch for this vulnerability, as listed in the VMware Advisory esx-202-200610-patch. See References.
For VMware ESX Server 2.1.3:
Apply the patch for this vulnerability, as listed in the VMware Advisory esx-213-200610-patch. See References.
For VMware 2.5.3:
Apply the patch for this vulnerability, as listed in the VMware Advisory esx-253-200610-patch. See References.
For other distributions:
Contact your vendor for upgrade or patch information.
Consequences:
Denial of Service
References:
- BugTraq Mailing List 20040113, 20040127 OpenSSH - Connection problem when LoginGraceTime exceeds time at http://marc.theaimsgroup.com/?l=openssh-unix-dev&m=107520317020444&q=raw.
- Full-Disclosure Mailing List, Mon Nov 13 2006 - 17:22:38 CST, VMSA-2006-0006 - VMware ESX Server 2.5.3 Upgrade Patch 4 at http://archives.neohapsis.com/archives/fulldisclosure/2006-11/0226.html.
- Full-Disclosure Mailing List, Mon Nov 13 2006 - 17:22:54 CST, VMSA-2006-0007 - VMware ESX Server 2.1.3 Upgrade Patch 2 at http://archives.neohapsis.com/archives/fulldisclosure/2006-11/0224.html.
- Full-Disclosure Mailing List, Mon Nov 13 2006 - 17:23:03 CST, VMSA-2006-0008 - VMware ESX Server 2.0.2 Upgrade Patch 2 at http://archives.neohapsis.com/archives/fulldisclosure/2006-11/0225.html.
- OpenSSH Web site, OpenSSH at http://www.openssh.org.
- VMware Advisory esx-253-200610-patch, VMware ESX Server 2.5.3 Upgrade Patch 4 (for 2.5.3 Systems Only) at http://www.vmware.com/download/esx/esx-253-200610-patch.html.
- VMware Web site, VMware ESX Server 2.1.3 Upgrade Patch 2 (for 2.1.3 Systems Only) at http://www.vmware.com/download/esx/esx-213-200610-patch.html.
- VMware Web site, VMware ESX Server 2.0.2 Upgrade Patch 2 (for 2.0.2 Systems Only) at http://www.vmware.com/download/esx/esx-202-200610-patch.html.
- BID-14963: OpenSSH LoginGraceTime Remote Denial Of Service Vulnerability
- CVE-2004-2069: sshd.c in OpenSSH 3.6.1p2 and 3.7.1p2 and possibly other versions, when using privilege separation, does not properly signal the non-privileged process when a session has been terminated after exceeding the LoginGraceTime setting, which leaves the connection open and allows remote attackers to cause a denial of service (connection consumption).
- OSVDB ID: 16567: OpenSSH Privilege Separation LoginGraceTime DoS
- RHSA-2005-550: openssh security update
- SA17252: Avaya Intuity LX Two Vulnerabilities
- SA22875: VMware ESX Server Multiple Vulnerabilities
- SA23680: VMWare ESX Server Multiple Vulnerabilities
- VUPEN/ADV-2006-4502: VMware ESX Server Security Update Fixes Multiple Buffer Overflow Vulnerabilities
Reported:
Dec 30, 2004
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