Bug ID 744186: JavaScript injection interferes with X-UA-Compatible meta http-equiv tag

Last Modified: Sep 14, 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,,,,, 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,,,,,, 15.0.0, 15.0.1,,,,

Opened: Sep 15, 2018

Severity: 4-Minor


Enabling any JavaScript injection interferes with <meta http-equiv="X-UA-Compatible" content="..."> when it is included in the HTML response from the back-end server.


The impact is that pages loaded in Internet Explorer may be loaded in compatibility mode instead of following the X-UA-Compatible header.


-- The back-end web server uses <meta http-equiv="X-UA-Compatible" content="..."> header in the HTML and relies on it for displaying Internet Explorer content. -- Users using Internet Explorer to access the Virtual Server -- JavaScript injection is enabled from any of the ASM features, such as: DoS Profile: Single Page Application Bot Defense Profile: Single Page Application, Verify After Access, Generate After Access ASM Policy: CSRF, AJAX Blocking Page, Web Scraping - Bot Detection


For injections coming from DoS or Bot Defense: Modify the DB variable which controls the location of the injection: -- tmsh modify sys db dosl7.parse_html_inject_tags value before,script,before,/head,before,body This will cause the script to be injected after the first <script> tag, or before the </head> tag, which ever comes first on the response HTML. For injections coming from the ASM Policy: -- /usr/share/ts/bin/add_del_internal add smart_inject 1 -- bigstart restart asm This will cause the JavaScript to be injected after the X-UA-Compatible header, if such header exists on the response HTML.

Fix Information


Behavior Change

Guides & references

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