Bug ID 621808: Proactive Bot Defense failing in IE11 with Compatibility View enabled

Last Modified: Jun 18, 2019

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

Fixed In:
13.0.0, 12.1.2

Opened: Oct 11, 2016
Severity: 3-Major

Symptoms

Microsoft Internet Explorer version 11 (IE11) browsers which have 'Compatibility View' enabled (under Compatibility View Settings IE11 menu), fail the JavaScript challenge when Proactive Bot Defense is enabled and the 'Block requests from suspicious browsers' checkbox is checked. The challenged request is blocked using a TCP_RST flag, and the browser displays 'This page can't be displayed'.

Impact

Legitimate browsers get blocked when accessing the site.

Conditions

-- DoS profile that is attached to the virtual server. -- Proactive Bot Defense is enabled -- The 'Block requests from suspicious browsers' checkbox is checked. -- IE11 browsers are in use. -- The site's domain is inserted to the 'Compatibility View Settings' in the browser's menu.

Workaround

None.

Fix Information

IE11 browsers with 'Compatibility View' enabled on the site no longer get blocked when Proactive Bot Defense is enabled on the DoS profile.

Behavior Change