{"id":"CVE-2021-40109","details":"A SSRF issue was discovered in Concrete CMS through 8.5.5. Users can access forbidden files on their local network. A user with permissions to upload files from external sites can upload a URL that redirects to an internal resource of any file type. The redirect is followed and loads the contents of the file from the redirected-to server. Files of disallowed types can be uploaded.","modified":"2026-04-10T04:37:45.140808Z","published":"2021-09-27T13:15:08.107Z","references":[{"type":"ADVISORY","url":"https://documentation.concretecms.org/developers/introduction/version-history/856-release-notes"},{"type":"REPORT","url":"https://hackerone.com/reports/1102105"}],"affected":[{"ranges":[{"type":"GIT","repo":"https://github.com/concretecms/concretecms","events":[{"introduced":"0"},{"fixed":"f9c8e08d3651a250f42e0c0a8cc18bc64b42733f"}],"database_specific":{"versions":[{"introduced":"0"},{"fixed":"8.5.6"}]}}],"versions":["5.7.0","5.7.0.1","5.7.0.3","5.7.0.4","5.7.1","5.7.2","5.7.2.1","5.7.3","5.7.3.1","5.7.4.1","5.7.5.2","5.7.5.5","5.7.5.6","5.7.5.7","8.1.0","8.2.0","8.2.0RC2","8.2.1","8.3.1","8.4.1"],"database_specific":{"source":"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2021-40109.json"}}],"schema_version":"1.7.5","severity":[{"type":"CVSS_V3","score":"CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:L/I:L/A:N"}]}