Paper/Archive/CVE-2026-55695

CVE-2026-55695

fearlessgeekmedia FearlessCMS — FearlessCMS: Remote Code Execution via Unvalidated Update Repository URL in System Updater

EPSS 0.5%public exploit CVSS 9.1

critical.is priorityof 100

CVSS 9.1 (CNA)9.1 / 10 × 3027.3 Not in CISA KEV+300.0 EPSS percentile 40.3.403 × 208.1 Exploit: SSVC poc+1010.0 SSVC exploitation: poc+100.0

Description · from the CVE record

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.

Affected

ProductAffectedFixed inSource

FearlessCMS< 0.1.3b–CNA

Scores by source

GitHub_M (CNA)9.1CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:C/C:H/I:H/A:H

CISA ADPSSVCExploitation: poc · Automatable: no · Technical impact: total

References

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