CVE-2026-8240CWE-284

Concrete CMS 9.5.0 and below is vulnerable to unauthenticated page metadata disclosure in Backend\SummaryTemplate

Medium · published May 21, 2026

CVSS v4.0
6.3
EPSS
0%
Percentile
24.3
In the wild
Unconfirmed
What it is

Concrete CMS 9.5.0 and below is vulnerable to unauthenticated page metadata disclosure across every page with a configured summary template, revealing the existence of private, draft, and restricted pages while leaking title, path, description, and author information. The Concrete CMS security team gave this vulnerability a CVSS v.4.0 score of 6.3 with vector CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:L/VI:N/VA:N/SC:N/SI:N/SA:N. Thanks Winston Crooker for reporting.

The record
Technical detail
CVSS v4.0
6.3 · MEDIUM
Vector
CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:L/VI:N/VA:N/SC:N/SI:N/SA:N
EPSS
0.00325 · 24.3th percentile
Weakness
CWE-284 · Improper Access Control
Published
2026-05-21T21:11Z
EPSS history
Timeline
  • 21 MAY 21:11Z
    Concrete CMS 9.5.0 and below is vulnerable to unauthenticated page metadata disclosure in Backend\SummaryTemplate
    cvelistv5