4.6 - RHSA-2016:0043

Problem Description:

Updated openssh packages that fix two security issues are now available for Red Hat Enterprise Linux 7.

Red Hat Product Security has rated this update as having Moderate security impact. Common Vulnerability Scoring System (CVSS) base scores, which give detailed severity ratings, are available for each vulnerability from the CVE links in the References section.

2. Relevant releases/architectures:

Red Hat Enterprise Linux Client (v. 7) - x86_64 Red Hat Enterprise Linux Client Optional (v. 7) - x86_64 Red Hat Enterprise Linux ComputeNode (v. 7) - x86_64 Red Hat Enterprise Linux ComputeNode Optional (v. 7) - x86_64 Red Hat Enterprise Linux Server (v. 7) - ppc64, ppc64le, s390x, x86_64 Red Hat Enterprise Linux Server Optional (v. 7) - ppc64, ppc64le, s390x, x86_64 Red Hat Enterprise Linux Workstation (v. 7) - x86_64 Red Hat Enterprise Linux Workstation Optional (v. 7) - x86_64

3. Description:

OpenSSH is OpenBSD's SSH (Secure Shell) protocol implementation. These packages include the core files necessary for both the OpenSSH client and server.

An information leak flaw was found in the way the OpenSSH client roaming feature was implemented. A malicious server could potentially use this flaw to leak portions of memory (possibly including private SSH keys) of a successfully authenticated OpenSSH client. (CVE-2016-0777)

A buffer overflow flaw was found in the way the OpenSSH client roaming feature was implemented. A malicious server could potentially use this flaw to execute arbitrary code on a successfully authenticated OpenSSH client if that client used certain non-default configuration options. (CVE-2016-0778)

Red Hat would like to thank Qualys for reporting these issues.

All openssh users are advised to upgrade to these updated packages, which contain backported patches to correct these issues. After installing this update, the OpenSSH server daemon (sshd) will be restarted automatically.

4. Solution:

Before applying this update, make sure all previously released errata relevant to your system have been applied.

For details on how to apply this update, refer to:

https://access.redhat.com/articles/11258

5. Bugs fixed (https://bugzilla.redhat.com/):

1298032 - CVE-2016-0777 OpenSSH: Client Information leak due to use of roaming connection feature 1298033 - CVE-2016-0778 OpenSSH: Client buffer-overflow when using roaming connections