Arbitrary file upload in Churchcrm Crm

CVE-2026-58409

ChurchCRM is an open-source church management system. Prior to version 7.4.0, an authenticated administrator can achieve Remote Code Execution (RCE) on the server by installing a malicious plugin ZIP archive containing a PHP webshell. The application explicitly includes 'php' in its ALLOWED_EXTENSIONS list, while the dangerous extensions denylist (DENIED_EXTENSIONS) fails to block standard .php files. Because `php` is explicitly included in the allowed extension list for plugin archives, and extracted files are placed directly under the web root, any PHP file inside the ZIP becomes immediately executable via HTTP — without even needing to "enable" the plugin through the application UI. The /plugins/install-url API route (management.php) allows an administrator to source the malicious ZIP from any attacker-controlled HTTPS URL, validating it only against an attacker-supplied SHA-256 hash. This issue has been fixed in version 7.4.0.

Vulnerability class: Unrestricted File Upload

Published · last modified .

CVSS v3 metric

CVSS v3 base score 9.1 (Critical). Vector: CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:C/C:H/I:H/A:H.

EPSS exploit prediction

EPSS: 0.008 (54.5th percentile), scored .

Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 54th percentile — 54.5% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS trend (30 days)EPSS over the last 30 days for CVE-2026-58409: held from 0.008 to 0.008.

EPSS over last 30 days · oldest: 0.008 · newest: 0.008 · change: 0.000

Affected products

Weakness classification (CWE)

References

Frequently asked questions

What is CVE-2026-58409?
CVE-2026-58409 is a critical-severity vulnerability in Churchcrm Crm, classified under Unrestricted Upload of File with Dangerous Type. CVSS score: 9.1/10. Published 2026-07-13.
How severe is CVE-2026-58409?
Critical severity. CVSS v3 base score is 9.1 out of 10.