Bug ID 790089: ASM SPA JavaScript code causes a web page to hang upon parallel ajax requests.

Last Modified: Jan 20, 2023

Bug Tracker

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

Known Affected Versions:
13.1.0,,,,,,,,, 13.1.1,,,,, 13.1.3,,,,,,, 13.1.4,, 13.1.5,, 14.0.0,,,,,, 14.0.1,, 14.1.0,,,,,, 14.1.2,,,,,,,,, 14.1.3,, 14.1.4,,,,,,, 14.1.5,,,, 15.0.0, 15.0.1,,,,

Fixed In:

Opened: Jun 05, 2019
Severity: 2-Critical


A web page hangs when parallel AJAX requests being sent.


Web-page processing halts; endless loading image is posted.


-- ASM provisioned. -- Single Page Application (SPA) enabled Bot Defense, DoS, or ASM Policy. -- Bot Defense, DoS, or ASM Policy attached to a virtual server. -- A web page sends two or more parallel AJAX requests.


The issue was introduced in the May-2019 live-update file. Rolling back to the Apr-2019 file avoids the issue.

Fix Information

ASM SPA JavaScript code has been fixed and avoids endless stack traversing.

Behavior Change