Last Modified: Feb 03, 2026
Affected Product(s):
BIG-IP LTM
Known Affected Versions:
17.1.2.1, 17.1.2.2, 17.1.3, 17.1.3.1
Opened: Jun 27, 2025 Severity: 3-Major
LTM Syncookie mode is stuck in software only for a virtual server.
One virtual server is in hardware SYN cookie mode, the other is in software SYN cookie mode.
- LTM provisioned, no AFM - Two identical virtual servers listening on different VLANs - SYN flood on both virtuals
tmsh modify sys db pvasyncookies.preferhwlmode value true reboot
None