9.8
CRITICAL CVSS 3.1
CVE-2026-109218
Contact Manager <= 9.1.2 - Unauthenticated Arbitrary File Upload via Trailing-Dot Filename Blacklist Bypass
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.

INFO

Published Date :

Oct. 28, 2026, 7:16 a.m.

Last Modified :

Oct. 28, 2026, 7:16 a.m.

Remotely Exploit :

Yes !
Affected Products

The following products are affected by CVE-2026-109218 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
The Common Vulnerability Scoring System is a standardized framework for assessing the severity of vulnerabilities in software and systems. We collect and displays CVSS scores from various sources for each CVE.
Score Version Severity Vector Exploitability Score Impact Score Source
CVSS 3.1 CRITICAL MITRE-CVE
CVSS 3.1 CRITICAL [email protected]
Solution
Update the Contact Manager plugin to the latest version to fix arbitrary file upload vulnerability.
  • Update the Contact Manager plugin to the latest version.
  • Ensure file upload validation is robust.
  • Remove uploaded files promptly after processing.
CWE - Common Weakness Enumeration

While CVE identifies specific instances of vulnerabilities, CWE categorizes the common flaws or weaknesses that can lead to vulnerabilities. CVE-2026-109218 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-2026-109218 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-2026-109218 vulnerability anywhere in the article.

The following table lists the changes that have been made to the CVE-2026-109218 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]

    Oct. 28, 2026

    Action Type Old Value New Value
    Added 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.
    Added CVSS V3.1 AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
    Added CWE CWE-434
    Added Affected New affected value received. <a href="https://github.com/CVEProject/cvelistV5/blob/main/cves/2026/109xxx/CVE-2026-109218.json">CVE-2026-109218</a>
    Added Reference https://fr.wordpress.org/plugins/contact-manager/
    Added Reference https://plugins.trac.wordpress.org/browser/contact-manager/tags/9.1.2/contact-manager.php#L42
    Added Reference https://plugins.trac.wordpress.org/browser/contact-manager/tags/9.1.2/includes/add-message.php#L254
    Added Reference https://plugins.trac.wordpress.org/browser/contact-manager/tags/9.1.2/includes/add-message.php#L256
    Added Reference https://plugins.trac.wordpress.org/browser/contact-manager/tags/9.1.2/includes/forms/processing.php#L102
    Added Reference https://plugins.trac.wordpress.org/changeset?reponame=&new=3767815%40contact-manager%2Ftags%2F9.1.3&old=3661172%40contact-manager%2Ftags%2F9.1.2
    Added Reference https://www.wordfence.com/threat-intel/vulnerabilities/id/b359ef59-4c2e-4d4e-b000-1845525131de?source=cve
EPSS is a daily estimate of the probability of exploitation activity being observed over the next 30 days. Following chart shows the EPSS score history of the vulnerability.