Bug ID 496621: Portal Access incorectly rewrites expressions with JavaScript typeof operator

Last Modified: Jan 20, 2023

Bug Tracker

Affected Product:  See more info
BIG-IP APM(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,, 14.1.0,,,,,, 14.1.2,,,,,,,,, 14.1.3,, 14.1.4,,,,,,, 14.1.5,,,

Opened: Dec 15, 2014
Severity: 4-Minor


The Portal Access module transforms intranet web application code to make it accessible via an APM virtual server. One of these transformations might incorrectly rewrite expressions with 'typeof' operator, though you might not see any immediate visible effect.


When Portal Access accesses the intranet application containing such code, expressions with typeof operator may have wrong value, leading application to incorrect code paths. As a result, the application might fail with a very obscure and difficult to diagnose errors.


The issue affects expressions like 'typeof something' where 'something' is expected to be transformed by Portal Access. For example, with the original code similar to 'var l = window.location; if (typeof l.href) {...}' unrewritten typeof argument causes condition to fail.


Use an iRule for each specific case. There is no global workaround.

Fix Information


Behavior Change