Virtual servers in F5 BIG-IP systems 11.2.1 HF11 through HF15, 11.4.1 HF4 through HF10, 11.5.3 through 11.5.4, 11.6.0 HF5 through HF7, and 12.0.0, when configured with a TCP profile, allow remote attackers to cause a denial of service (Traffic Management Microkernel restart) via crafted network traffic.