CVE-2016-10009 Red Hat Update for openssh (RHSA-2017:2029)

OpenSSH is an SSH protocol implementation supported by a number of Linux, UNIX, and similar operating systems.

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)

Affected Products
Red Hat Enterprise Linux Server 7 x86_64
Red Hat Enterprise Linux Workstation 7 x86_64
Red Hat Enterprise Linux Desktop 7 x86_64
Red Hat Enterprise Linux for IBM z Systems 7 s390x
Red Hat Enterprise Linux for Power, big endian 7 ppc64
Red Hat Enterprise Linux for Scientific Computing 7 x86_64
Red Hat Enterprise Linux for Power, little endian 7 ppc64le
Red Hat Enterprise Linux Server for ARM 7 aarch64

A remote unauthenticated attacker could possibly use this flaw to determine valid user names by measuring the timing of server responses. (CVE-2016-6210)
A remote unauthenticated attacker could use this flaw to temporarily trigger high CPU consumption in sshd by sending long passwords. (CVE-2016-6515)
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)
An attacker able to compromise the privilege-separated process could therefore obtain the leaked key information. (CVE-2016-10011)
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)

Upgrade to the latest packages which contain a patch. Refer to Applying Package Updates to RHEL system for details.

Refer to Red Hat security advisory RHSA-2017:2029 to address this issue and obtain more information.

Patch:
Following are links for downloading patches to fix the vulnerabilities:

RHSA-2017:2029: Red Hat Enterprise Linux