SOL15927 - BIND vulnerability CVE-2014-8500

*The LTM and GTM modules are not vulnerable by default. To be vulnerable, recursion must be manually enabled in the BINDnamed.conffile.

Recommended Action

If the previous table lists a version in the Versions known to be not vulnerablecolumn, 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 is responding to this vulnerability as determined by the parameters defined in SOL4602: Overview of the F5 security vulnerability response policy.

Determining if recursion has been manually enabled on the system

1. Log in to the BIG-IP command line.

2. Type the following command:

grep recursion /var/named/config/named.conf

3. If the command returns the following response, recursion has been enabled, and you should perform the following, Mitigating the vulnerability procedure.

recursion yes;

If the command returns the following response, recursion has not been enabled, and the system is not vulnerable.

recursion no;

Mitigating the vulnerability

To mitigate this vulnerability, you can turn recursion off in the named.conf file. To do so, perform the following procedure:

Impact of action: This modification requires a change to your configuration, and you should test it in an appropriate environment before implementing it.

1. Log in to the BIG-IP command line.
2. Change directories to the /var/named/configdirectory by typing the following command:

cd /var/named/config

3. Create a backup of the named.conf file by typing the following command:

cp named.conf named.conf.SOL15927

4. To edit the named.conf file, locate the** recursion** option, for example:

recursion yes;

5. Change the recursion option to** no**, for example:

recursion no;

6. Save the changes to the named.conf file.
7. Restart namedto allow the changes to reload by typing the following command:

bigstart restart named

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