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ESB-2014.2508 - [Appliance] F5 products: Denial of service - Remote/unauthenticated

Date: 23 December 2014
References: ESB-2014.2323  ESB-2014.2324  ESB-2014.2350  ESB-2014.2390  ESB-2015.0046  ESB-2015.0138.4  ESB-2015.0477  ESB-2015.0940  

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             AUSCERT External Security Bulletin Redistribution

                SOL15927: BIND vulnerability CVE-2014-8500
                             23 December 2014


        AusCERT Security Bulletin Summary

Product:           F5 products
Publisher:         F5 Networks
Operating System:  Network Appliance
Impact/Access:     Denial of Service -- Remote/Unauthenticated
Resolution:        Mitigation
CVE Names:         CVE-2014-8500  

Reference:         ESB-2014.2390

Original Bulletin:

- --------------------------BEGIN INCLUDED TEXT--------------------

SOL15927: BIND vulnerability CVE-2014-8500

Security AdvisorySecurity Advisory

Original Publication Date: 12/19/2014

Updated Date: 12/19/2014


ISC BIND 9.0.x through 9.8.x, 9.9.0 through 9.9.6, and 9.10.0 through 9.10.1 
does not limit delegation chaining, which allows remote attackers to cause a 
denial of service (memory consumption and named crash) via a large or infinite
number of referrals. (CVE-2014-8500)


This behavior may lead to resource exhaustion and denial-of-service (up to and
including termination of the named server process.) All recursive resolvers 
are affected. Authoritative servers may be affected if an attacker can control
a delegation traversed by the authoritative server in servicing the zone.

Important: Recursion is not enabled by default for BIG-IP modules.


F5 Product Development has assigned ID 492367 (BIG-IP) to this vulnerability,
and has evaluated the currently supported releases for potential 

To determine if your release is known to be vulnerable, the components or 
features that are affected by the vulnerability, and for information about 
releases or hotfixes that address the vulnerability, refer to the following 

Product 		Versions known to be vulnerable 		Versions known to be not vulnerable 		Vulnerable component or feature

BIG-IP LTM 		11.0.0 - 11.6.0 
			10.1.0 - 10.2.4 				None 						BIND*

BIG-IP AAM 		None 						11.4.0 - 11.6.0 				None

BIG-IP AFM 		None 						11.3.0 - 11.6.0 				None

BIG-IP Analytics 	None 						11.0.0 - 11.6.0 				None

BIG-IP APM None		11.0.0 - 11.6.0					10.1.0 - 10.2.4 				None

BIG-IP ASM 		None						11.0.0 - 11.6.0
									10.1.0 - 10.2.4 				None

BIG-IP Edge Gateway 	None						11.0.0 - 11.3.0
									10.1.0 - 10.2.4 				None

BIG-IP GTM 		11.0.0 - 11.6.0
			10.1.0 - 10.2.4 				None 						BIND*

BIG-IP Link Controller 	None						11.0.0 - 11.6.0
									10.1.0 - 10.2.4 				None

BIG-IP PEM 		None 						11.3.0 - 11.6.0 				None

BIG-IP PSM 		None						11.0.0 - 11.4.1
									10.0.0 - 10.2.4 				None

BIG-IP WebAccelerator 	None						11.0.0 - 11.3.0
									10.0.0 - 10.2.4 				None

BIG-IP WOM 		None						11.0.0 - 11.3.0
									10.0.0 - 10.2.4 				None

ARX 			None 						6.2.0 - 6.4.0 					None

Enterprise Manager 	None 						3.0.0 - 3.1.1
									2.1.0 - 2.3.0 					None

FirePass 		None 						7.0.0
									6.0.0 - 6.1.0 					None

BIG-IQ Cloud 		None 						4.0.0 - 4.4.0 					None

BIG-IQ Device 		None 						4.2.0 - 4.4.0 					None

BIG-IQ Security 	None 						4.0.0 - 4.4.0 					None

*The LTM and GTM modules are not vulnerable by default. In order to be 
vulnerable, recursion must be manually enabled in the BIND named.conf file.

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 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

To determine if recursion has been manually enabled on the system, perform the
following procedure:

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 will require a change to your 
configuration, and should be tested in an appropriate environment prior to 

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

2. Change directories to the /var/named/config directory by typing the following

   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 named to 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.

SOL4602: Overview of the F5 security vulnerability response policy

SOL4918: Overview of the F5 critical issue hotfix policy

- --------------------------END INCLUDED TEXT--------------------

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