In some circumstances, the Traffic Management Microkernel (TMM) does not properly handle certain malformed Websockets requests/responses, which allows remote attackers to cause a denial-of-service (DoS) or possible remote code execution on the F5 BIG-IP system running versions 13.0.0 - 13.1.0.3 or 12.1.0 - 12.1.3.1.

On F5 BIG-IP 13.1.0-13.1.0.3, 13.0.0, 12.1.0-12.1.3.3, 11.6.1-11.6.3.1, 11.5.1-11.5.5, or 11.2.1, a malformed TLS handshake causes TMM to crash leading to a disruption of service. This issue is only exposed on the data plane when Proxy SSL configuration is enabled. The control plane is not impacted by this issue.

On F5 BIG-IP versions 13.0.0 - 13.1.0.3, attackers may be able to disrupt services on the BIG-IP system with maliciously crafted client certificate. This vulnerability affects virtual servers associated with Client SSL profile which enables the use of client certificate authentication. Client certificate authentication is not enabled by default in Client SSL profile. There is no control plane exposure.