CVE record
CVE-2026-8421
Concrete CMS 9.5.0 and below contains a CSRF vulnerability in the install_package() method of concrete/controllers/single_page/dashboard/extend/install.php. An attacker who can cause an authenticated administrator to visit a crafted page, and who has placed or caused a package to be present under DIR_PACKAGES/<handle>/, can force the installation of that package without any CSRF protection. Package installation executes the package controller's install() method as the web server user, enabling remote code execution. In order to be vulnerable, the victim must be passing canInstallPackages. 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.
Amazon picks for vulnerability response
Product discovery links are localized to Amazon US when country data is available.
This page may contain affiliate links. We may earn a commission at no extra cost to you. As an Amazon Associate I earn from qualifying purchases.
Hardware security keys
Physical MFA keys for admin accounts, cloud consoles, password managers, and incident response workflows.
Security engineering books
Books on secure design, incident response, threat modeling, cloud security, and practical defense.
Ethernet cable testers
Portable testers for validating office, rack, home lab, and troubleshooting cable runs.
Vulnerability metadata
- Published
- 2026-05-21T15:46:34.107Z
- Modified
- 2026-05-21T15:46:34.107Z
- EPSS
- Not available
- 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/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
Recommended platforms
Affiliate-supported recommendations for CVE-2026-8421 vulnerability response.
This page may contain affiliate links. We may earn a commission at no extra cost to you. As an Amazon Associate I earn from qualifying purchases.
Security engineering books
Browse practical security, incident response, cloud security, and secure coding books for team learning.
Cloud security platform
Continuously review cloud posture, exposed services, identity risks, and misconfigurations.
Monitoring and incident response
Track uptime, logs, traces, TLS expiry, API latency, and production security signals.