Bug ID 740719: ASM CSP header parser does not honor unsafe-inline attribute within script-src directive

Last Modified: Jul 12, 2023

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

Known Affected Versions:
13.0.0, 13.0.0 HF1, 13.0.0 HF2, 13.0.0 HF3, 13.0.1, 13.1.0,,,,,,,,, 13.1.1, 14.0.0,,,,

Fixed In:

Opened: Aug 16, 2018

Severity: 3-Major


Browser reports Content-Security-Policy error when ASM modifies the 'Content-Security-Policy' (CSP) header.


Browser posts 'Content-Security-Policy' error and stops JavaScript execution.


1. ASM provisioned. 2. ASM policy attached to a virtual server. 3. CSRF or Ajax blocking page enabled within ASM policy 4. Backend server sends 'Content-Security-Policy' header with 'script-src' 'unsafe-inline' directive.


Disable 'Content-Security-Policy' header parsing for ASM policies. To do so, follow these steps: 1. In /usr/share/ts/bin/add_del_internal, run the following command: add csp_enabled 0 2. Restart ASM by running the following command: bigstart restart asm

Fix Information

ASM 'Content-Security-Policy' header parser no longer modifies the 'Content-Security-Policy' header when there is 'script-src' 'unsafe-inline' directive arriving from a backend server. This is correct behavior.

Behavior Change

Guides & references

K10134038: F5 Bug Tracker Filter Names and Tips