CentOS 4 / 5 : openssh (CESA-2008:0855)

high Nessus Plugin ID 43708



The remote CentOS host is missing one or more security updates.


Updated openssh packages are now available for Red Hat Enterprise Linux 4, Red Hat Enterprise Linux 5, and Red Hat Enterprise Linux 4.5 Extended Update Support.

This update has been rated as having critical security impact by the Red Hat Security Response Team.

OpenSSH is OpenBSD's SSH (Secure SHell) protocol implementation.

Last week Red Hat detected an intrusion on certain of its computer systems and took immediate action. While the investigation into the intrusion is on-going, our initial focus was to review and test the distribution channel we use with our customers, Red Hat Network (RHN) and its associated security measures. Based on these efforts, we remain highly confident that our systems and processes prevented the intrusion from compromising RHN or the content distributed via RHN and accordingly believe that customers who keep their systems updated using Red Hat Network are not at risk. We are issuing this alert primarily for those who may obtain Red Hat binary packages via channels other than those of official Red Hat subscribers.

In connection with the incident, the intruder was able to sign a small number of OpenSSH packages relating only to Red Hat Enterprise Linux 4 (i386 and x86_64 architectures only) and Red Hat Enterprise Linux 5 (x86_64 architecture only). As a precautionary measure, we are releasing an updated version of these packages, and have published a list of the tampered packages and how to detect them at http://www.redhat.com/security/data/openssh-blacklist.html

To reiterate, our processes and efforts to date indicate that packages obtained by Red Hat Enterprise Linux subscribers via Red Hat Network are not at risk.

These packages also fix a low severity flaw in the way ssh handles X11 cookies when creating X11 forwarding connections. When ssh was unable to create untrusted cookie, ssh used a trusted cookie instead, possibly allowing the administrative user of a untrusted remote server, or untrusted application run on the remote server, to gain unintended access to a users local X server. (CVE-2007-4752)


Update the affected openssh packages.

See Also




Plugin Details

Severity: High

ID: 43708

File Name: centos_RHSA-2008-0855.nasl

Version: 1.19

Type: local

Agent: unix

Published: 1/6/2010

Updated: 1/4/2021

Supported Sensors: Agentless Assessment, Frictionless Assessment Agent, Frictionless Assessment AWS, Frictionless Assessment Azure

Risk Information


Risk Factor: Medium

Score: 5.9


Risk Factor: High

Base Score: 9.3

Temporal Score: 6.9

Vector: AV:N/AC:M/Au:N/C:C/I:C/A:C

Temporal Vector: E:U/RL:OF/RC:C

Vulnerability Information

CPE: p-cpe:/a:centos:centos:openssh, p-cpe:/a:centos:centos:openssh-askpass, p-cpe:/a:centos:centos:openssh-askpass-gnome, p-cpe:/a:centos:centos:openssh-clients, p-cpe:/a:centos:centos:openssh-server, cpe:/o:centos:centos:4, cpe:/o:centos:centos:5

Required KB Items: Host/local_checks_enabled, Host/CentOS/release, Host/CentOS/rpm-list

Exploit Ease: No known exploits are available

Patch Publication Date: 8/23/2008

Vulnerability Publication Date: 9/11/2007

Reference Information

CVE: CVE-2007-4752, CVE-2008-3844

BID: 25628, 30794

RHSA: 2008:0855

CWE: 20