Bug ID 643155: ASM JavaScript features fail when LTM Policy has a default rule which disables ASM

Last Modified: Nov 07, 2022

Bug Tracker

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

Known Affected Versions:
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, 12.1.2, 12.1.2 HF1, 12.1.2 HF2, 12.1.3,,,,,,,, 12.1.4,, 12.1.5,,,, 12.1.6, 13.0.0, 13.0.0 HF1, 13.0.0 HF2, 13.0.0 HF3, 13.0.1, 13.1.0,,,,,,,,, 13.1.1,,,,, 13.1.3,,,,,,, 13.1.4,, 13.1.5,, 14.0.0,,,,,, 14.0.1,

Opened: Feb 03, 2017
Severity: 4-Minor


The JavaScript features in the ASM Policy utilize requests to /TSbd/* URLs which are handled by the BIG-IP and not sent to the back-end server. When there is an LTM Policy which has a default rule of "asm disable", these URLs will not be handled by bd, and will be sent to the back-end server, which typically responds with 404 Not Found, causing these features to fail. The impacted features are: * Web Scraping Bot Detection * AJAX Blocking Page * CSRF Protection * Single-Page Application * Client-Side mitigation of Web Scraping Session Opening * Client-Side mitigation of Brute Force


Legitimate requests may get blocked.


LTM Policy has a default rule which disables ASM.


If the LTM Policy has a default rule which disables ASM, then the workaround is to add a rule in the LTM Policy so that all requests to URL /TSbd/* go to the ASM Policy (any policy could be used for this case).

Fix Information


Behavior Change