{"id":"CVE-2026-8417","url":"https://www.cyber-defence.io/tools/cve/CVE-2026-8417","generatedAt":"2026-10-28T03:25:09.086Z","title":"Concrete CMS 9.5.0 and below does not validate a CSRF token before processing requests to /dashboard/extend/update/do_update/<pkgHandle>.","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.","published":"2026-05-21T21:16:34.000Z","lastModified":"2026-07-23T16:10:00.000Z","status":"Analyzed","sourceIdentifier":"ff5b8ace-8b95-4078-9743-eac1ca5451de","cvss":{"version":"4.0","score":7.5,"severity":"HIGH","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/M"},"cwe":["CWE-352"],"affected":["concretecms/concrete cms"],"epss":{"score":0.00122,"percentile":0.01941,"date":"2026-10-26","history":[]},"kev":{"listed":false},"exploits":{"count":0,"verified":false,"firstPublished":null,"source":"Exploit-DB (https://gitlab.com/exploit-database/exploitdb)","entries":[]},"verdict":{"level":"high","text":"High impact if exploited, but EPSS currently rates exploitation as unlikely (0.12%). Schedule it in the normal patch cycle and watch for a rise in EPSS or a public exploit."},"changes":[],"references":[{"url":"https://documentation.concretecms.org/9-x/developers/introduction/version-history/951-release-notes","tags":["Release Notes"],"source":"ff5b8ace-8b95-4078-9743-eac1ca5451de"}],"sources":{"nvd":"https://nvd.nist.gov/vuln/detail/CVE-2026-8417","epss":"https://www.first.org/epss/","kev":"https://www.cisa.gov/known-exploited-vulnerabilities-catalog","exploitdb":"https://www.exploit-db.com/"},"licence":"CC BY 4.0 — link back to the CVE Explorer if you publish the results; upstream data remains subject to its own terms."}