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.
References7
- fr.wordpress.org/plugins/contact-manager/
- plugins.trac.wordpress.org/browser/contact-manager/tags/9.1.2/c…
- plugins.trac.wordpress.org/browser/contact-manager/tags/9.1.2/i…
- plugins.trac.wordpress.org/browser/contact-manager/tags/9.1.2/i…
- plugins.trac.wordpress.org/browser/contact-manager/tags/9.1.2/i…
- plugins.trac.wordpress.org/changeset?reponame=&new=3767815%40co…
- www.wordfence.com/threat-intel/vulnerabilities/id/b359ef59-4c2e…
Metrics
- CVSS 3.1
-
9.8
CRITICAL
Score source: CNA
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H - EPSS — exploit probability
- 1% percentile: 51 · as of 2 November 2026
- CWE
- CWE-434
Could this be exploited in your environment?
A patch closes the known hole. A penetration test shows what an attacker can still reach — with proof.