In F5 BIG-IP LTM, AAM, AFM, APM, ASM, Link Controller, PEM, and WebSafe 12.1.0 through 12.1.2, certain values in a TLS abbreviated handshake when using a client SSL profile with the Session Ticket option enabled may cause disruption of service to the Traffic Management Microkernel (TMM). The Session Ticket option is disabled by default.

When the F5 BIG-IP 12.1.0-12.1.1, 11.6.0-11.6.1, 11.5.1-11.5.5, or 11.2.1 system is configured with a wildcard IPSec tunnel endpoint, it may allow a remote attacker to disrupt or impersonate the tunnels that have completed phase 1 IPSec negotiations. The attacker must possess the necessary credentials to negotiate the phase 1 of the IPSec exchange to exploit this vulnerability; in many environment this limits the attack surface to other endpoints under the same administration.