CentOS 7 : openssh (CESA-2017:2029)

high Nessus Plugin ID 102751

Synopsis

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

Description

An update for openssh is now available for Red Hat Enterprise Linux 7.

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.

The following packages have been upgraded to a later upstream version:
openssh (7.4p1). (BZ#1341754)

Security Fix(es) :

* A covert timing channel flaw was found in the way OpenSSH handled authentication of non-existent users. A remote unauthenticated attacker could possibly use this flaw to determine valid user names by measuring the timing of server responses. (CVE-2016-6210)

* It was found that OpenSSH did not limit password lengths for password authentication. A remote unauthenticated attacker could use this flaw to temporarily trigger high CPU consumption in sshd by sending long passwords. (CVE-2016-6515)

* It was found that ssh-agent could load PKCS#11 modules from arbitrary paths. An attacker having control of the forwarded agent-socket on the server, and the ability to write to the filesystem of the client host, could use this flaw to execute arbitrary code with the privileges of the user running ssh-agent. (CVE-2016-10009)

* It was found that the host private key material could possibly leak to the privilege-separated child processes via re-allocated memory. An attacker able to compromise the privilege-separated process could therefore obtain the leaked key information. (CVE-2016-10011)

* It was found that the boundary checks in the code implementing support for pre-authentication compression could have been optimized out by certain compilers. An attacker able to compromise the privilege-separated process could possibly use this flaw for further attacks against the privileged monitor process. (CVE-2016-10012)

Additional Changes :

For detailed information on changes in this release, see the Red Hat Enterprise Linux 7.4 Release Notes linked from the References section.

Solution

Update the affected openssh packages.

See Also

http://www.nessus.org/u?5ff4711b

Plugin Details

Severity: High

ID: 102751

File Name: centos_RHSA-2017-2029.nasl

Version: 3.7

Type: local

Agent: unix

Published: 8/25/2017

Updated: 1/4/2021

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

Risk Information

VPR

Risk Factor: Medium

Score: 5.9

CVSS v2

Risk Factor: High

Base Score: 7.8

Temporal Score: 6.1

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

CVSS Score Source: CVE-2016-6515

CVSS v3

Risk Factor: High

Base Score: 7.8

Temporal Score: 7

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

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

Vulnerability Information

CPE: p-cpe:/a:centos:centos:openssh, p-cpe:/a:centos:centos:openssh-askpass, p-cpe:/a:centos:centos:openssh-cavs, p-cpe:/a:centos:centos:openssh-clients, p-cpe:/a:centos:centos:openssh-keycat, p-cpe:/a:centos:centos:openssh-ldap, p-cpe:/a:centos:centos:openssh-server, p-cpe:/a:centos:centos:openssh-server-sysvinit, p-cpe:/a:centos:centos:pam_ssh_agent_auth, cpe:/o:centos:centos:7

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

Exploit Available: true

Exploit Ease: Exploits are available

Patch Publication Date: 8/23/2017

Vulnerability Publication Date: 8/7/2016

Reference Information

CVE: CVE-2016-10009, CVE-2016-10011, CVE-2016-10012, CVE-2016-10708, CVE-2016-6210, CVE-2016-6515

RHSA: 2017:2029