SOL17242 - Linux kernel SCTP vulnerability CVE-2015-1421

Note: As of February 17, 2015, AskF5 Security Advisory articles include the Severity value. Security Advisory articles published before this date do not list a Severity value.

*The BIG-IP/BIG-IQ/Enterprise Manager software contains vulnerable code (SCTP kernel module), but the code is not enabled by default. Before a remote attacker can exploit this vulnerability, a locally authenticated administrative user must load the vulnerable SCTP kernel module, create a listener (such as self IP) on the control plane, and allow SCTP traffic on this listener. Because of the specific conditions required for exploit, F5 Product Development considers affected BIG-IP/BIG-IQ/Enterprise Manager systems as not vulnerable in a standard configuration and severely vulnerable if the described conditions are met.

Recommended Action

If the previous table lists a version in the Versions known to be not vulnerable column, you can eliminate this vulnerability by upgrading to the listed version. If the listed version is older than the version you are currently running, or if the table does not list any version in the column, then no upgrade candidate currently exists.

F5 responds to vulnerabilities in accordance with the Severity values published in the previous table. The Severity values and other security vulnerability parameters are defined in SOL4602: Overview of the F5 security vulnerability response policy.

BIG-IP/BIG-IQ/Enterprise Manager

If you must load the vulnerable SCTP kernel module for your environment, F5 recommends that you block upstream traffic to the control plane of the affected systems. To mitigate this vulnerability for an affected system, you should permit access to the management interface, and/or the self IP that exposes SCTP listeners, over a secure network.

Traffix SDC

To mitigate this vulnerability for an affected system, you should use iptables rules to limit SCTP access to trusted users only.

Supplemental Information

• SOL9970: Subscribing to email notifications regarding F5 products
• SOL9957: Creating a custom RSS feed to view new and updated documents
• SOL4918: Overview of the F5 critical issue hotfix policy
• SOL167: Downloading software and firmware from F5