---
id: CVE-2026-55695
title: >-
  FearlessCMS is a flat-file content management system centered on simplicity
  and open source
summary: >-
  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
  perf…
severity: critical
cvss: 9.1
cvssVector: 'CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:C/C:H/I:H/A:H'
cwe:
  - CWE-94
published: '2026-10-13'
updated: '2026-10-13'
sourceUpdated: '2026-10-13T17:17:42.283'
source: NVD
sourceUrl: 'https://nvd.nist.gov/vuln/detail/CVE-2026-55695'
references:
  - url: >-
      https://github.com/fearlessgeekmedia/FearlessCMS/commit/6dba91d496463e3940a2c917af3cae97b191de92
    label: security-advisories@github.com
  - url: 'https://github.com/fearlessgeekmedia/FearlessCMS/pull/64'
    label: security-advisories@github.com
  - url: 'https://github.com/fearlessgeekmedia/FearlessCMS/releases/tag/0.1.3'
    label: security-advisories@github.com
  - url: >-
      https://github.com/fearlessgeekmedia/FearlessCMS/security/advisories/GHSA-56wm-3q3v-m93m
    label: security-advisories@github.com
  - url: >-
      https://github.com/fearlessgeekmedia/FearlessCMS/security/advisories/GHSA-56wm-3q3v-m93m
    label: 134c704f-9b21-4f2e-91b3-4a467353bcc0
tags:
  - nvd
ingestedAt: '2026-10-13T16:35:46.743Z'
---

## Overview

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.

## Remediation

Refer to the linked advisories for vendor-supplied fixes and affected version ranges.