SECURELYN

CVE-2026-55695

FearlessCMS is a flat-file content management system centered on simplicity and open source. In 0.1.2b and earlier, an authenticated administrator can set an arbitrary Git repository URL through admin/updater-handler.php and trigger perform_update, which passes the URL to update.sh. The updater clones the repository and replaces the live plugins/, admin/, and includes/ directories without verifying the repository's identity, signatures, or contents. Because router.php permits existing PHP files under plugins to be executed by the PHP development server, attacker-supplied update content can ex…

Scores

9.1
CVSS 9.1 out of 10, critical severity.
0.5%
EPSS 0.5% chance of exploitation in the next 30 days.

The facts

Published
13 October 2026
Last changed
16 October 2026
NVD status
Deferred
Severity
Critical, CVSS 9.1 out of 10 (version 3.1)
CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:C/C:H/I:H/A:H
Weakness
Known exploited
Not in the CISA Known Exploited Vulnerabilities catalogue in this build.
EPSS
0.5% chance of exploitation activity in the next 30 days (percentile 39).

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References