Bug ID 504031: document.write()/document.writeln() redefinition does not work

Last Modified: Jul 18, 2026

Affected Product(s):
BIG-IP APM(all modules)

Known Affected Versions:
11.5.3, 11.5.3 hf1, 11.5.3 hf2, 11.5.4, 11.5.4 hf1, 11.5.4 hf2, 11.5.4 hf3, 11.5.4 hf4, 11.5.5, 11.5.6, 11.5.7, 11.5.8, 11.5.9, 11.5.10, 11.6.0, 11.6.0 hf1, 11.6.0 hf2, 11.6.0 hf3, 11.6.0 hf4, 11.6.0 hf5, 11.6.0 hf6, 11.6.0 hf7, 11.6.0 hf8, 11.6.1, 11.6.1 hf1, 11.6.1 hf2, 11.6.2, 11.6.2 hf1, 11.6.3, 11.6.3.1, 11.6.3.2, 11.6.3.3, 11.6.3.4, 11.6.4, 11.6.5, 11.6.5.1, 11.6.5.2, 11.6.5.3

Fixed In:
12.0.0

Opened: Jan 30, 2015

Severity: 3-Major

Symptoms

document.write()/document.writeln() redefinition does not work. Initial function is used instead.

Impact

Web application layout an/or logic can be broken.

Conditions

When web application JavaScript tries to redefine document.write() and/or document.writeln().

Workaround

None

Fix Information

Web application JavaScript can successfully redefine document.write and document.writeln.

Behavior Change

Guides & references

K10134038: F5 Bug Tracker Filter Names and Tips