VULNERABILITY INTELLIGENCE
CVE-2026-2717
CVSS score5.5 MEDIUM
EPSS probability0.47%
CISA KEVNot currently listed
Published2026-04-22
Last modified2026-06-17
CVSS vectorCVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:N/I:L/A:H
Description
The HTTP Headers plugin for WordPress is vulnerable to CRLF Injection in all versions up to, and including, 1.19.2. This is due to insufficient sanitization of custom header name and value fields before writing them to the Apache .htaccess file via `insert_with_markers()`. This makes it possible for authenticated attackers, with Administrator-level access and above, to inject arbitrary newline characters and additional Apache directives into the .htaccess configuration file via the 'Custom Headers' settings, leading to Apache configuration parse errors and potential site-wide denial of service.
Weakness classification
- CWE-93: Improper Neutralization of CRLF Sequences ('CRLF Injection')