CVE-2026-2717
HTTP Headers <= 1.19.2 - Authenticated (Administrator+) CRLF Injection via Custom Header Values
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.
INFO
Published Date :
April 22, 2026, 9:16 a.m.
Last Modified :
April 22, 2026, 9:16 a.m.
Remotely Exploit :
Yes !
Source :
[email protected]
Affected Products
The following products are affected by CVE-2026-2717
vulnerability.
Even if cvefeed.io is aware of the exact versions of the
products
that
are
affected, the information is not represented in the table below.
No affected product recoded yet
CVSS Scores
| Score | Version | Severity | Vector | Exploitability Score | Impact Score | Source |
|---|---|---|---|---|---|---|
| CVSS 3.1 | MEDIUM | [email protected] |
Solution
- Update the HTTP Headers plugin to the latest version.
- Review and sanitize custom header inputs.
- Validate .htaccess file content after changes.
References to Advisories, Solutions, and Tools
Here, you will find a curated list of external links that provide in-depth
information, practical solutions, and valuable tools related to
CVE-2026-2717.
CWE - Common Weakness Enumeration
While CVE identifies
specific instances of vulnerabilities, CWE categorizes the common flaws or
weaknesses that can lead to vulnerabilities. CVE-2026-2717 is
associated with the following CWEs:
Common Attack Pattern Enumeration and Classification (CAPEC)
Common Attack Pattern Enumeration and Classification
(CAPEC)
stores attack patterns, which are descriptions of the common attributes and
approaches employed by adversaries to exploit the CVE-2026-2717
weaknesses.
We scan GitHub repositories to detect new proof-of-concept exploits. Following list is a collection of public exploits and proof-of-concepts, which have been published on GitHub (sorted by the most recently updated).
Results are limited to the first 15 repositories due to potential performance issues.
The following list is the news that have been mention
CVE-2026-2717 vulnerability anywhere in the article.
The following table lists the changes that have been made to the
CVE-2026-2717 vulnerability over time.
Vulnerability history details can be useful for understanding the evolution of a vulnerability, and for identifying the most recent changes that may impact the vulnerability's severity, exploitability, or other characteristics.
-
New CVE Received by [email protected]
Apr. 22, 2026
Action Type Old Value New Value Added 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. Added CVSS V3.1 AV:N/AC:L/PR:H/UI:N/S:U/C:N/I:L/A:H Added CWE CWE-93 Added Reference https://plugins.trac.wordpress.org/browser/http-headers/tags/1.19.2/http-headers.php#L1098 Added Reference https://plugins.trac.wordpress.org/browser/http-headers/tags/1.19.2/http-headers.php#L745 Added Reference https://plugins.trac.wordpress.org/browser/http-headers/trunk/http-headers.php#L1098 Added Reference https://plugins.trac.wordpress.org/browser/http-headers/trunk/http-headers.php#L745 Added Reference https://www.wordfence.com/threat-intel/vulnerabilities/id/7716e77f-e899-4046-9421-86fc0c36c245?source=cve