Bug ID 1229861: Signature rule : regex "i" modifier should be translated into "nocase", instead of prepending "(?i)"

Last Modified: Feb 10, 2023

Bug Tracker

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

Known Affected Versions:
16.1.0, 16.1.1, 16.1.2,,, 16.1.3,,,

Opened: Jan 24, 2023
Severity: 5-Cosmetic


The "i" modifier is translated into "(?i)" that does not corresponds with matchCase flag ("Case Sensitive" option in GUI) in the control plane. This may introduce a confusion when user writes a regex with "i" in advanced mode, and switch to simple mode. User would expect "Case Sensitive" option is unchecked to "i", but in GUI it displays as checked. The matching behavior is as configured with "i", case-insensitive.


Possible confusion in GUI.


In advanced mode, configure following pattern with "i" modifier. re2:"/abc/Vi"; norm;


Use "nocase" modifier instead.

Fix Information


Behavior Change