{"id":"CVE-2025-48953","aliases":["GHSA-fr6r-p8hv-x3c4"],"url":"https://o3.security/vulnerability/CVE-2025-48953","summary":"Umbraco Vulnerable to By-Pass of Configured Allowed Extensions for File Uploads","details":"Umbraco is an ASP.NET content management system (CMS). Starting in version 14.0.0 and prior to versions 15.4.2 and 16.0.0, it's possible to upload a file that doesn't adhere with the configured allowable file extensions via a manipulated API request. The issue is patched in versions 15.4.2 and 16.0.0. No known workarounds are available.","published":"2025-06-03T18:19:28.771Z","modified":"2026-08-12T03:51:35.549731574Z","cvss":{"score":5.5,"severity":"MEDIUM","vector":"CVSS:3.1/AV:N/AC:H/PR:L/UI:R/S:C/C:L/I:L/A:L"},"epss":null,"cisaKev":null,"exploitsKnown":0,"affectedPackages":[{"ecosystem":"NuGet","name":"Umbraco.Cms","fixedVersion":"15.4.2"}],"fix":{"url":"https://github.com/umbraco/Umbraco-CMS/commit/d920e93d1ee29dc3301697e444f53e8cd5db3cf9","label":"umbraco/Umbraco-CMS@d920e93"},"references":[{"type":"ADVISORY","url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2025/48xxx/CVE-2025-48953.json"},{"type":"ADVISORY","url":"https://github.com/umbraco/Umbraco-CMS/security/advisories/GHSA-fr6r-p8hv-x3c4"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2025-48953"},{"type":"FIX","url":"https://github.com/umbraco/Umbraco-CMS/commit/d920e93d1ee29dc3301697e444f53e8cd5db3cf9"}],"provenance":{"sources":["OSV.dev","FIRST.org (EPSS)"],"lastVerified":"2026-08-12T03:51:35.549731574Z"}}