Vulnerability · Published Apr 22, 2026 · Assigned by Wordfence

CVE-2026-2717HTTP Headers <= 1.19.2 - Authenticated (Administrator+) CRLF Injection via Custom Header Values

Medium 5.5

In plain English

A medium-severity security flaw in HTTP Headers from zinoui. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 0.5% (higher than 41% of all known vulnerabilities).

Severity (CVSS 3.1)5.5Medium

Exploit odds (30 days)0.5%top 58.8% of all CVEs

Exploited in the wildNo reportsCISA SSVC: none

Attack toolingNoneno public tooling known

Official 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.

Affected products (as reported)

Vendor	Product	Versions
zinoui	HTTP Headers	0 – through 1.19.2

Weakness: CWE-93 · Vector: CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:N/I:L/A:H

In plain English

Official description

Affected products (as reported)

References