Bug ID 691806: RFC 793 - behavior receiving FIN/ACK in SYN-RECEIVED state

Last Modified: Sep 13, 2023

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

Known Affected Versions:
11.2.1, 11.3.0, 11.4.0, 11.4.1, 11.5.0, 11.5.1, 11.5.2, 11.5.3, 11.5.4, 11.5.5, 11.5.6, 11.6.0, 11.6.1, 11.6.2, 11.6.3, 11.6.3.1, 11.6.3.2, 12.0.0, 12.0.0 HF1, 12.1.0 HF1, 12.0.0 HF2, 12.1.0 HF2, 12.0.0 HF3, 12.0.0 HF4, 12.1.1 HF1, 12.1.1 HF2, 12.1.2 HF1, 12.1.2 HF2, 12.1.0, 12.1.1, 12.1.2, 12.1.3, 12.1.3.1, 12.1.3.2, 12.1.3.3, 12.1.3.4, 12.1.3.5, 13.0.0, 13.0.0 HF1, 13.0.0 HF2, 13.0.0 HF3, 13.0.1, 13.1.0, 13.1.0.1, 13.1.0.2, 13.1.0.3

Fixed In:
14.0.0, 13.1.0.4, 12.1.3.6, 11.6.3.3, 11.5.7

Opened: Oct 31, 2017

Severity: 3-Major

Related Article: K61815412

Symptoms

The BIG-IP system resets connection with RST if it receives FIN/ACK in SYN-RECEIVED state.

Impact

The BIG-IP system resets connection with RST.

Conditions

The BIG-IP system receives FIN/ACK when it is in SYN-RECEIVED state.

Workaround

None.

Fix Information

The BIG-IP system now responds with FIN/ACK to early FIN/ACK.

Behavior Change

Guides & references

K10134038: F5 Bug Tracker Filter Names and Tips