CVE-2026-8417

HIGH EPSS 2.3%
Published May 21, 20261mo ago · Modified Jun 17, 20262w ago
7.5 CVSS 4.0
High
Find Similar
Published May 21, 2026 1mo ago
Last Modified Jun 17, 2026 2w ago

Description

Concrete CMS 9.5.0 and below does not validate a CSRF token before processing requests to /dashboard/extend/update/do_update/<pkgHandle>. The do_update() method in concrete/controllers/single_page/dashboard/extend/update.php checks only canInstallPackages() before executing upgradeCoreData() and upgrade() on the named package's controller. Because the endpoint is a state-changing GET route with no token enforcement, an attacker can force an authenticated administrator to trigger a package upgrade via a single cross-site navigation.In order to be vulnerable, the victim must be passing canInstallPackages() and and a target package must already be already installed. The Concrete CMS security team gave this vulnerability a CVSS v.4.0 score of 7.5 with vector CVSS:4.0/AV:N/AC:H/AT:P/PR:N/UI:A/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N. Thanks  https://github.com/maru1009  for reporting.

CVSS Details

Base Score
7.5
Exploitability
Impact
Vector string
CVSS:4.0/AV:N/AC:H/AT:P/PR:N/UI:A/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X
Attack Vector Network
Attack Complexity High
Privileges Required None
User Interaction A
Scope X

Threat Intelligence

EPSS Exploit Probability
2.3% percentile
Exploit & Patch Status
No Known Exploit
No Patch Available

Weaknesses 1

CWE-352 Cross-Site Request Forgery (CSRF) Authentication

Affected Products 1

VendorProductVersionRange
concretecmsconcrete_cms* <9.5.1

References 1

Remediation

No remediation data recorded yet

Check vendor advisories and the NVD entry for patch availability.