Bug ID 561500: ICAP Parsing improvement

Last Modified: Oct 06, 2020

Bug Tracker

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

Known Affected Versions:
11.6.0, 11.6.0 HF1, 11.6.0 HF2, 11.6.0 HF3, 11.6.0 HF4, 11.6.0 HF5, 11.6.0 HF6, 11.6.0 HF7, 11.6.0 HF8, 11.6.1, 12.0.0, 12.0.0 HF1, 12.0.0 HF2, 12.0.0 HF3, 12.0.0 HF4, 12.1.0, 12.1.0 HF1, 12.1.0 HF2, 12.1.1, 12.1.1 HF1, 12.1.1 HF2

Fixed In:
13.0.0, 12.1.2, 11.6.1 HF1

Opened: Dec 04, 2015
Severity: 4-Minor


If a malformed ICAP message is sent to the Big-IP the ICAP parser can enter a state where it consumes an increasing amount of CPU and memory.


Memory and CPU usage increase. Eventually the TMM may crash causing Big-IP fail-over.


A request-adapt or response-adapt profile is configured. An ICAP message is received from an ICAP server lacking "ICAP/1.0" as initial header line.



Fix Information

ICAP parser checks for correct initial ICAP/1.0 header line and rejects message if missing.

Behavior Change