Bug ID 1710233: No option to disable violation for double-escaped NULL in query string

Last Modified: Sep 15, 2025

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

Known Affected Versions:
17.1.1.4, 17.1.2, 17.1.2.1, 17.1.2.2

Opened: Oct 27, 2024

Severity: 3-Major

Symptoms

Requests containing double-escaped NULL characters (e.g., %2500) trigger a violation, even when single-escaped NULL (%00) detection is desired.

Impact

May result in false positives for legitimate traffic using double-escaped characters, with no available configuration to suppress this specific violation.

Conditions

Occurs when ASM is configured to detect NULL characters in query strings. There is currently no granular control to differentiate between %00 and %2500.

Workaround

None

Fix Information

None

Behavior Change

Guides & references

K10134038: F5 Bug Tracker Filter Names and Tips