F5 BIG-IP LTM, AFM, Analytics, APM, ASM, Link Controller, and PEM 11.3.x, 11.4.x before 11.4.1 HF10, 11.5.x before 11.5.4, 11.6.x before 11.6.1, and 12.x before 12.0.0 HF1; BIG-IP AAM 11.4.x before 11.4.1 HF10, 11.5.x before 11.5.4, 11.6.x before 11.6.1, and 12.x before 12.0.0 HF1; BIG-IP DNS 12.x before 12.0.0 HF1; BIG-IP Edge Gateway, WebAccelerator, and WOM 11.3.0; BIG-IP GTM 11.3.x, 11.4.x before 11.4.1 HF10, 11.5.x before 11.5.4, and 11.6.x before 11.6.1; BIG-IP PSM 11.3.x and 11.4.x before 11.4.1 HF10; Enterprise Manager 3.0.0 through 3.1.1; BIG-IQ Cloud and BIG-IQ Security 4.0.0 through 4.5.0; BIG-IQ Device 4.2.0 through 4.5.0; BIG-IQ ADC 4.5.0; BIG-IQ Centralized Management 4.6.0; and BIG-IQ Cloud and Orchestration 1.0.0 on the 3900, 6900, 8900, 8950, 11000, 11050, PB100 and PB200 platforms, when software SYN cookies are configured on virtual servers, allow remote attackers to cause a denial of service (High-Speed Bridge hang) via an invalid TCP segment.
https://support.f5.com/kb/en-us/solutions/public/k/35/sol35358312.html