---
id: CVE-2026-88418
title: >-
  CMSimple 5.24 ships with CSRF protection disabled by default, which turns
  csrfProtection() into a no-op on every state-changing admin request, and it
  does not send the csrf_token hidden field in admin forms
summary: >-
  CMSimple 5.24 ships with CSRF protection disabled by default, which turns
  csrfProtection() into a no-op on every state-changing admin request, and it
  does not send the csrf_token hidden field in admin forms. Because
  administrator authent…
severity: high
cvss: 8.8
cvssVector: 'CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H'
cwe:
  - CWE-352
published: '2026-09-22'
updated: '2026-09-26'
sourceUpdated: '2026-09-26T00:16:37.843'
source: NVD
sourceUrl: 'https://nvd.nist.gov/vuln/detail/CVE-2026-88418'
references:
  - url: 'https://github.com/15536818056/CVE/issues/5'
    label: cve@mitre.org
  - url: 'https://github.com/15536818056/CVE/issues/5'
    label: 134c704f-9b21-4f2e-91b3-4a467353bcc0
tags:
  - nvd
  - cve.org
  - exploit-available
exploitAvailable: true
ssvc:
  exploitation: poc
  automatable: 'no'
  technicalImpact: total
  timestamp: '2026-09-25T23:23:56.913674Z'
epss: 0.00328
epssPercentile: 0.23274
ingestedAt: '2026-09-22T20:10:15.101Z'
---

## Overview

CMSimple 5.24 ships with CSRF protection disabled by default, which turns csrfProtection() into a no-op on every state-changing admin request, and it does not send the csrf_token hidden field in admin forms. Because administrator authentication is cookie-only and no CSRF token is enforced, an unauthenticated attacker can induce a logged-in administrator's browser to issue a forged content-save request with a text payload containing a scripting marker. The marker is stored verbatim into content/content.php; on every subsequent page view evaluate_cmsimple_scripting() (functions.php) executes the marker body with PHP eval() — for all visitors, including unauthenticated ones. This yields persistent remote code execution on the web server.

## Remediation

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