Vulnerability in fearlessgeekmedia FearlessCMS

[ Why it matters ]Priority signals

• Public proof-of-concept exploit exists (CISA SSVC)
• Critical severity: CVSS 9.1

[ Description ]Official 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.

[ Fixes ]Fixes and patches

No fix or interim patch is linked from our sources yet. Check the vendor references below and limit exposure of affected systems until a fix is available.

[ References ]References

• github.com/fearlessgeekmedia/FearlessCMS/commit/6dba91d496463e3940a2c917af3cae97b191de92
• github.com/fearlessgeekmedia/FearlessCMS/pull/64
• github.com/fearlessgeekmedia/FearlessCMS/releases/tag/0.1.3
• github.com/fearlessgeekmedia/FearlessCMS/security/advisories/GHSA-56wm-3q3v-m93m