Bug ID 1017557: ASM Plugin Abort reset for chunked response without proper terminating 0 chunk followed by FIN

Last Modified: Sep 23, 2021

Bug Tracker

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

Known Affected Versions:
15.1.0, 15.1.0.1, 15.1.0.2, 15.1.0.3, 15.1.0.4, 15.1.0.5, 15.1.1, 15.1.2, 15.1.2.1, 15.1.3, 15.1.3.1, 15.1.4

Opened: May 11, 2021
Severity: 3-Major

Symptoms

ASM BD sends a reset back to the client when the backend server sends a response without proper terminating 0 chunk followed by FIN.

Impact

Valid requests can be reset.

Conditions

- ASM provisioned - ASM policy attached to a virtual server - Backed server sends a bad chunked response

Workaround

Any one of the following workarounds can be applied. -- Fix backed server behavior. -- Fix bad response using iRule, appending proper terminating 0 chunk -- Change ASM internal /usr/share/ts/bin/add_del_internal update bypass_upon_load 1

Fix Information

None

Behavior Change