Get the latest updates on how F5 mitigates Heartbleed

The Heartbleed attack in OpenSSL 1.0.1 and beyond allows an attacker to get up to 64k of process data from a TLS heartbeat response. The 64k of data will quite often contain sensitive information such as keys or passwords. There are quite a few exploits in the wild already for this attack.

F5 has analyzed this attack and we are pleased to say that BIG-IP data traffic using an SSL profile with default ciphers is not vulnerable to this attack. BIG-IP SSL profiles terminate the SSL traffic on the BIG-IP, so the malicious heartbeat never gets to your webservers. TLS heartbeats are not enabled on current versions of BIG-IP, so any virtual server protected by an SSL profile is not vulnerable.

However, if you are not using the SSL termination capabilities of the BIG-IP, then the attack will pass directly through the BIG-IP and to the webservers. You may be vulnerable depending on the webservers you use.

BIG-IP versions 11.5.0 and 11.5.1 do use OpenSSL 1.0.1 for the management GUI and are vulnerable to the attack. Versions of BIG-IP older than 11.5 are not vulnerable.

F5 encourages using a private management network that is not connected to the internet.

A hotfix is available for the management GUI.

Get the latest updates on how F5 mitigates Heartbleed

See the AskF5 solution for more information.

A mitigation for virtual servers that do not use SSL termination

If you are using a simple load balancing virtual server without an SSL profile, then the traffic is passing directly to your webservers.

My great F5 colleagues and I have written an iRule that mitigates this vulnerability when the client sends a heartbeat. Since we haven't seen a valid client that sends heartbearts, we like this solution. If you have clients that do send valid heartbeats, then we have an iRule that watches for large heartbeat responses and kills the connection before they are sent to the client.