RHEL 7 : openssh (RHSA-2017:2029)

high Nessus Plugin ID 102112

Synopsis

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

Description

The remote Redhat Enterprise Linux 7 host has packages installed that are affected by multiple vulnerabilities as referenced in the RHSA-2017:2029 advisory.

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.

Tenable has extracted the preceding description block directly from the Red Hat Enterprise Linux security advisory.

Note that Nessus has not tested for these issues but has instead relied only on the application's self-reported version number.

Solution

Update the affected packages.

See Also

http://www.nessus.org/u?59bed70f

http://www.nessus.org/u?e109ca23

https://access.redhat.com/errata/RHSA-2017:2029

https://access.redhat.com/security/updates/classification/#moderate

https://bugzilla.redhat.com/show_bug.cgi?id=1357442

https://bugzilla.redhat.com/show_bug.cgi?id=1360973

https://bugzilla.redhat.com/show_bug.cgi?id=1364935

https://bugzilla.redhat.com/show_bug.cgi?id=1366400

https://bugzilla.redhat.com/show_bug.cgi?id=1373835

https://bugzilla.redhat.com/show_bug.cgi?id=1375179

https://bugzilla.redhat.com/show_bug.cgi?id=1381997

https://bugzilla.redhat.com/show_bug.cgi?id=1396400

https://bugzilla.redhat.com/show_bug.cgi?id=1398569

https://bugzilla.redhat.com/show_bug.cgi?id=1402424

https://bugzilla.redhat.com/show_bug.cgi?id=1406269

https://bugzilla.redhat.com/show_bug.cgi?id=1406286

https://bugzilla.redhat.com/show_bug.cgi?id=1406293

https://bugzilla.redhat.com/show_bug.cgi?id=1418062

https://bugzilla.redhat.com/show_bug.cgi?id=1420910

https://bugzilla.redhat.com/show_bug.cgi?id=1438414

https://bugzilla.redhat.com/show_bug.cgi?id=1450361

Plugin Details

Severity: High

ID: 102112

File Name: redhat-RHSA-2017-2029.nasl

Version: 3.12

Type: local

Agent: unix

Published: 8/2/2017

Updated: 3/15/2025

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

Risk Information

VPR

Risk Factor: Medium

Score: 5.9

Vendor

Vendor Severity: Moderate

CVSS v2

Risk Factor: High

Base Score: 7.5

Temporal Score: 5.9

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

CVSS Score Source: CVE-2016-10009

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

CVSS Score Source: CVE-2016-10012

Vulnerability Information

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

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

Exploit Available: true

Exploit Ease: Exploits are available

Patch Publication Date: 8/1/2017

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

CWE: 20, 200, 287, 385, 770

RHSA: 2017:2029