RHEL 6 : openssh (RHSA-2016:0741)

critical Nessus Plugin ID 91073

Synopsis

The remote Red Hat host is missing one or more security updates.

Description

An update for openssh is now available for Red Hat Enterprise Linux 6.

Red Hat Product Security has rated this update as having a security impact of Moderate. A Common Vulnerability Scoring System (CVSS) base score, which gives a detailed severity rating, is available for each vulnerability from the CVE link(s) in the References section.

OpenSSH is an SSH protocol implementation supported by a number of Linux, UNIX, and similar operating systems. It includes the core files necessary for both the OpenSSH client and server.

Security Fix(es) :

* It was found that the OpenSSH client did not properly enforce the ForwardX11Timeout setting. A malicious or compromised remote X application could possibly use this flaw to establish a trusted connection to the local X server, even if only untrusted X11 forwarding was requested. (CVE-2015-5352)

* A flaw was found in the way OpenSSH handled PAM authentication when using privilege separation. An attacker with valid credentials on the system and able to fully compromise a non-privileged pre-authentication process using a different flaw could use this flaw to authenticate as other users. (CVE-2015-6563)

* A use-after-free flaw was found in OpenSSH. An attacker able to fully compromise a non-privileged pre-authentication process using a different flaw could possibly cause sshd to crash or execute arbitrary code with root privileges. (CVE-2015-6564)

* An access flaw was discovered in OpenSSH; the OpenSSH client did not correctly handle failures to generate authentication cookies for untrusted X11 forwarding. A malicious or compromised remote X application could possibly use this flaw to establish a trusted connection to the local X server, even if only untrusted X11 forwarding was requested. (CVE-2016-1908)

For detailed information on changes in this release, see the Red Hat Enterprise Linux 6.8 Release Notes and Red Hat Enterprise Linux 6.8 Technical Notes linked from the References section.

Solution

Update the affected packages.

See Also

https://access.redhat.com/errata/RHSA-2016:0741

https://access.redhat.com/security/cve/cve-2015-5352

https://access.redhat.com/security/cve/cve-2015-6563

https://access.redhat.com/security/cve/cve-2015-6564

https://access.redhat.com/security/cve/cve-2016-1908

Plugin Details

Severity: Critical

ID: 91073

File Name: redhat-RHSA-2016-0741.nasl

Version: 2.12

Type: local

Agent: unix

Published: 5/12/2016

Updated: 10/24/2019

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

Risk Information

VPR

Risk Factor: Medium

Score: 6.7

CVSS v2

Risk Factor: High

Base Score: 7.5

Temporal Score: 5.5

Vector: CVSS2#AV:N/AC:L/Au:N/C:P/I:P/A:P

CVSS v3

Risk Factor: Critical

Base Score: 9.8

Temporal Score: 8.5

Vector: CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

Temporal Vector: CVSS:3.0/E:U/RL:O/RC:C

Vulnerability Information

CPE: p-cpe:/a:redhat:enterprise_linux:openssh, p-cpe:/a:redhat:enterprise_linux:openssh-askpass, p-cpe:/a:redhat:enterprise_linux:openssh-clients, p-cpe:/a:redhat:enterprise_linux:openssh-debuginfo, p-cpe:/a:redhat:enterprise_linux:openssh-ldap, p-cpe:/a:redhat:enterprise_linux:openssh-server, p-cpe:/a:redhat:enterprise_linux:pam_ssh_agent_auth, cpe:/o:redhat:enterprise_linux:6

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

Exploit Ease: No known exploits are available

Patch Publication Date: 5/10/2016

Vulnerability Publication Date: 8/2/2015

Reference Information

CVE: CVE-2015-5352, CVE-2015-6563, CVE-2015-6564, CVE-2016-1908

RHSA: 2016:0741