Bug ID 686926: IPsec: responder N(cookie) in SA_INIT response handled incorrectly

Last Modified: Nov 07, 2022

Bug Tracker

Affected Product:  See more info
BIG-IP LTM(all modules)

Known Affected Versions:
12.1.0, 12.1.0 HF1, 12.1.0 HF2, 12.1.1, 12.1.1 HF1, 12.1.1 HF2, 12.1.2, 12.1.2 HF1, 12.1.2 HF2, 12.1.3,,,,,, 13.0.0, 13.0.0 HF1, 13.0.0 HF2, 13.0.0 HF3, 13.0.1, 13.1.0,,,,,,,,, 13.1.1,,

Fixed In:

Opened: Oct 03, 2017
Severity: 3-Major


IKEv2 negotiation fails when a responder uses N(cookie) in the SA_INIT response, because the BIG-IP system does not expect a second response with the same zero message_id always used by SA_INIT.


The SA negotiation fails when a responder includes N(cookie) in a SA_INIT response, because a second response appears to have an out-of-order message ID when BIG-IP believe the first message_id of zero was already handled earlier.


Any time a responder sends N(cookie) in the first response to SA_INIT from a BIG-IP initiator.



Fix Information

The BIG-IP system now correctly tracks a need to receive a SECOND response with message_id zero, to finish the SA_INIT exchange, whenever the first SA_INIT response caused the BIG-IP system to resend the first request with the cookie included.

Behavior Change