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The form is rendered as a POST form, meaning the token reaches the browser, but because the controller discards it without verification, an attacker can craft a cross-site POST that triggers a core CMS update to an attacker-specified version string.  In order to be vulnerable, theictim must be passing canUpgrade()anda valid update version must be present under DIR_CORE_UPDATES. 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.","state":"PUBLISHED","assigner":"ConcreteCMS","published_at":"2026-05-21 21:16:34","updated_at":"2026-05-26 14:57:02"},"problem_types":["CWE-352","CWE-829","CWE-352 CWE-352 Cross-Site request forgery (CSRF)","CWE-829 CWE-829 Inclusion of functionality from untrusted control 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