HTTP Headers <= 1.19.2 - Authenticated (Administrator+) CRLF Injection via Custom Header Values
Key facts
- Attack vector
- Network
- Privileges required
- High
- User interaction
- None
- Attack complexity
- Low
- Impact type
- —
- Confidentiality · integrity · availability
- None · Low · High
- Fix status
- No fix listed
Attack profile from CVSS 3.1 · CNA. Fix status from CNA.
Summary
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.
Why it matters now
SSVC decision points
CISA ADP · SSVC 2.0.3
- Exploitation
- None
- Automatable
- No
- Technical impact
- Partial
The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.
Affected products
Remediation
No fixed version listed by the sources yet.
Timeline
- 2026-10-02 Threatist record created from CVE-2026-2717
- 2026-10-03 Alias added: GHSA-r256-59w3-3gr2
References
Other 5
- https://www.wordfence.com/threat-intel/vulnerabilities/id/7716e77f-e899-4046-9421-86fc0c36c245?source=cve
- https://plugins.trac.wordpress.org/browser/http-headers/tags/1.19.2/http-headers.php#L1098
- https://plugins.trac.wordpress.org/browser/http-headers/trunk/http-headers.php#L1098
- https://plugins.trac.wordpress.org/browser/http-headers/tags/1.19.2/http-headers.php#L745
- https://plugins.trac.wordpress.org/browser/http-headers/trunk/http-headers.php#L745
More zinoui vulnerabilities
- TI-2026-03581 HTTP Headers <= 1.19.2 - Authenticated (Administrator+) External Control of File Name or… CVSS 3.1HIGH 7.2
- TI-2026-01081 HTTP Headers <= 1.19.2 - Authenticated (Administrator+) Stored Cross-Site Scripting via 'Custom Headers' Plugin Setting CVSS 3.1MEDIUM 4.4
Sources
- CVE-2026-2717 · CVE Program
- CVE-2026-2717 · NVD
- FIRST EPSS
- GHSA-r256-59w3-3gr2 · GitHub Advisory Database · CC BY 4.0
This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences