openssh security update

2006-10-02T01:42:56
ID CESA-2006:0698-01
Type centos
Reporter CentOS Project
Modified 2006-10-02T01:42:56

Description

CentOS Errata and Security Advisory CESA-2006:0698-01

OpenSSH is OpenBSD's SSH (Secure SHell) protocol implementation. This package includes the core files necessary for both the OpenSSH client and server.

Mark Dowd discovered a signal handler race condition in the OpenSSH sshd server. A remote attacker could possibly leverage this flaw to cause a denial of service (crash). (CVE-2006-5051) The OpenSSH project believes the likelihood of successful exploitation leading to arbitrary code execution appears remote. However, the Red Hat Security Response Team have not yet been able to verify this claim due to lack of upstream vulnerability information. We are therefore including a fix for this flaw and have rated it important security severity in the event our continued investigation finds this issue to be exploitable.

Tavis Ormandy of the Google Security Team discovered a denial of service bug in the OpenSSH sshd server. A remote attacker can send a specially crafted SSH-1 request to the server causing sshd to consume a large quantity of CPU resources. (CVE-2006-4924)

An arbitrary command execution flaw was discovered in the way scp copies files locally. It is possible for a local attacker to create a file with a carefully crafted name that could execute arbitrary commands as the user running scp to copy files locally. (CVE-2006-0225)

The SSH daemon, when restricting host access by numeric IP addresses and with VerifyReverseMapping disabled, allows remote attackers to bypass "from=" and "user@host" address restrictions by connecting to a host from a system whose reverse DNS hostname contains the numeric IP address. (CVE-2003-0386)

All users of openssh should upgrade to these updated packages, which contain backported patches that resolve these issues.

Merged security bulletin from advisories: http://lists.centos.org/pipermail/centos-announce/2006-October/013310.html

Affected packages: openssh openssh-askpass openssh-askpass-gnome openssh-clients openssh-server

Upstream details at: https://rhn.redhat.com/errata/rh21as-errata.html