Vulnerability Description
The Contact Manager plugin for WordPress is vulnerable to Arbitrary File Upload in all versions up to, and including, 9.1.2 via the add_message function. This is due to an incomplete extension blacklist that fails to detect dangerous extensions when a trailing dot causes the extension-derivation routine to return an empty string, which sanitize_file_name() then silently removes before the file is written to disk. This makes it possible for unauthenticated attackers to upload files that may be executable, which makes remote code execution possible. Successful code execution additionally requires the server to use Apache with libapache2-mod-php (which maps .phar to PHP by default) and the attacker to retrieve the uploaded file within the brief window before it is removed by unlink() at end of request.
CVSS Score
CRITICAL
Related Weaknesses (CWE)
References
- https://fr.wordpress.org/plugins/contact-manager/
- https://plugins.trac.wordpress.org/browser/contact-manager/tags/9.1.2/contact-ma
- https://plugins.trac.wordpress.org/browser/contact-manager/tags/9.1.2/includes/a
- https://plugins.trac.wordpress.org/browser/contact-manager/tags/9.1.2/includes/a
- https://plugins.trac.wordpress.org/browser/contact-manager/tags/9.1.2/includes/f
- https://plugins.trac.wordpress.org/changeset?reponame=&new=3767815%40contact-man
- https://www.wordfence.com/threat-intel/vulnerabilities/id/b359ef59-4c2e-4d4e-b00
FAQ
What is CVE-2026-109218?
CVE-2026-109218 is a vulnerability with a CVSS score of 9.8 (CRITICAL). The Contact Manager plugin for WordPress is vulnerable to Arbitrary File Upload in all versions up to, and including, 9.1.2 via the add_message function. This is due to an incomplete extension blackli...
How severe is CVE-2026-109218?
CVE-2026-109218 has been rated CRITICAL with a CVSS base score of 9.8/10. This is considered a critical vulnerability requiring immediate attention.
Is there a patch for CVE-2026-109218?
Check the references section above for vendor advisories and patch information. Review vendor security bulletins for remediation guidance.