{"id":56202,"date":"2026-05-21T17:32:53","date_gmt":"2026-05-21T17:32:53","guid":{"rendered":"https:\/\/zero.redgem.net\/?p=56202"},"modified":"2026-05-21T17:32:53","modified_gmt":"2026-05-21T17:32:53","slug":"concrete-950-and-below-has-file-usage-disclosure-via-missing-permission-check-in-usage-controller","status":"publish","type":"post","link":"https:\/\/zero.redgem.net\/?p=56202","title":{"rendered":"Concrete 9.5.0 and below has file usage disclosure via missing permission check in Usage controller_CVE-2026-6826"},"content":{"rendered":"<p>{&#8220;lastseen&#8221;:&#8221;&#8221;,&#8221;description&#8221;:&#8221;Concrete CMS 9.5.0 and below\u00a0 is vulnerable to\u00a0unauthenticated file usage disclosure via missing permission check in the usage controller.\u00a0\u00a0Any unauthenticated visitor can request \/ccm\/system\/dialogs\/file\/usage\/{fID} with any file ID and receive a list of every page that references that file, including page IDs, handles, and full URLs. 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