CVE-2026-2717
HTTP Headers <= 1.19.2 - Authenticated (Administrator+) CRLF Injection via Custom Header Values
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.
Attack profile
How easy it is to exploit
- Attack vector
- Network
- Complexity
- Low
- Privileges needed
- High
- User interaction
- None
What an attacker can affect
- Confidentiality
- None
- Integrity
- Low
- Availability
- High
Exploit likelihood
What each source reports
CVE List Score used
5.5
HTTP Headers <= 1.19.2 - Authenticated (Administrator+) CRLF Injection via Custom Header Values
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.
- Record
CVE-2026-2717- CVSS 3.1
- 5.5 Medium
CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:N/I:L/A:H - Weakness
- CWE-93
- Updated
- 2026-11-02
EUVDEUVD-2026-24637
5.5
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.
- Record
EUVD-2026-24637- CVSS 3.1
- 5.5 Medium
CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:N/I:L/A:H - Updated
- 2026-11-02
GitHub AdvisoriesGHSA-r256-59w3-3gr2
5.5
The HTTP Headers plugin for WordPress is vulnerable to CRLF Injection in all versions up to, and...
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.
- Record
GHSA-r256-59w3-3gr2- CVSS 3.1
- 5.5 Medium
CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:N/I:L/A:H - Weakness
- CWE-93
- Updated
- 2026-11-02
NVD
5.5
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.
- Record
CVE-2026-2717- CVSS 3.1
- 5.5 Medium
CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:N/I:L/A:H - Weakness
- CWE-93
- Updated
- 2026-11-02
Affected products
History
| Recorded | Changed | Sources |
|---|---|---|
| first indexed | CVE List, EUVD, GitHub Advisories, NVD |
Dates are when Every CVE recorded each change. Upstream dates may differ.
In short
CVE-2026-2717 is a medium vulnerability (CVSS 5.5) in Zinoui Http Headers, published April 22, 2026. No source lists public exploit code. EPSS puts the chance of exploitation in the next 30 days at 0.47%, the 41st percentile. No source names a fixed version.
References
wordfence.com/threat-intel/vulnerabilities/id/7716e77f-e899-4046-9421-86fc0c36c245?source=cve
plugins.trac.wordpress.org/browser/http-headers/tags/1.19.2/http-headers.php
plugins.trac.wordpress.org/browser/http-headers/trunk/http-headers.php
nvd.nist.gov/vuln/detail/CVE-2026-2717
github.com/advisories/GHSA-r256-59w3-3gr2