Description
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 execute arbitrary PHP with the web server process's privileges and persist as a backdoor. This issue is fixed in version 0.1.3b.
References5
- github.com/fearlessgeekmedia/FearlessCMS/commit/6dba91d496463e3…
- github.com/fearlessgeekmedia/FearlessCMS/pull/64
- github.com/fearlessgeekmedia/FearlessCMS/releases/tag/0.1.3
- github.com/fearlessgeekmedia/FearlessCMS/security/advisories/GH…
- github.com/fearlessgeekmedia/FearlessCMS/security/advisories/GH…
Metrics
- CVSS 3.1
-
9.1
CRITICAL
Score source: CNA
CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:C/C:H/I:H/A:H - EPSS — exploit probability
- 0% percentile: 41 · as of 11 November 2026
- CWE
- CWE-94
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.