Bug ID 420485: TMM silently drop non-SYN packet without TCP RST

Last Modified: Jul 12, 2023

Affected Product(s):
BIG-IP LTM(all modules)

Known Affected Versions:
10.2.4, 11.3.0, 11.4.0, 11.4.1

Fixed In:
11.5.0, 11.4.1 HF9

Opened: May 03, 2013

Severity: 4-Minor

Related Article: K15048


In 11.0.0 and 11.3.0, TMM silently drops the non-SYN packet without TCP RST if TCP 3WHS has not yet established. In 11.2.1, TMM sends the reset. In 10.2.3, TMM rejects non-SYN packet.


When this occurs, there is no RST for non-SYN packets.


TMM rejects non-SYN packet if TCP 3WHS has not yet established.



Fix Information

TMM now correctly sends a RST packet when it receives a non-SYN TCP packet for which no connection has been established. In some versions, TMM would silently drop the packet.

Behavior Change

Guides & references

K10134038: F5 Bug Tracker Filter Names and Tips