diff --git a/advisories/github-reviewed/2025/06/GHSA-fr6r-p8hv-x3c4/GHSA-fr6r-p8hv-x3c4.json b/advisories/github-reviewed/2025/06/GHSA-fr6r-p8hv-x3c4/GHSA-fr6r-p8hv-x3c4.json
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@@ -0,0 +1,68 @@
+{
+  "schema_version": "1.4.0",
+  "id": "GHSA-fr6r-p8hv-x3c4",
+  "modified": "2025-06-04T23:50:55Z",
+  "published": "2025-06-04T23:50:55Z",
+  "aliases": [
+    "CVE-2025-48953"
+  ],
+  "summary": "Umbraco Vulnerable to By-Pass of Configured Allowed Extensions for File Uploads",
+  "details": "### Impact\nVia a manipulated API request it's possible to upload a file that doesn't adhere with the configured allowable file extensions.\n\n### Patches\nPatched in 15.4.2 and 16.0.0.\n\n### Workarounds\nNone available.",
+  "severity": [
+    {
+      "type": "CVSS_V3",
+      "score": "CVSS:3.1/AV:N/AC:H/PR:L/UI:R/S:C/C:L/I:L/A:L"
+    }
+  ],
+  "affected": [
+    {
+      "package": {
+        "ecosystem": "NuGet",
+        "name": "Umbraco.Cms"
+      },
+      "ranges": [
+        {
+          "type": "ECOSYSTEM",
+          "events": [
+            {
+              "introduced": "14.0.0"
+            },
+            {
+              "fixed": "15.4.2"
+            }
+          ]
+        }
+      ],
+      "database_specific": {
+        "last_known_affected_version_range": "<= 15.4.1"
+      }
+    }
+  ],
+  "references": [
+    {
+      "type": "WEB",
+      "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": "WEB",
+      "url": "https://github.com/umbraco/Umbraco-CMS/commit/d920e93d1ee29dc3301697e444f53e8cd5db3cf9"
+    },
+    {
+      "type": "PACKAGE",
+      "url": "https://github.com/umbraco/Umbraco-CMS"
+    }
+  ],
+  "database_specific": {
+    "cwe_ids": [
+      "CWE-434"
+    ],
+    "severity": "MODERATE",
+    "github_reviewed": true,
+    "github_reviewed_at": "2025-06-04T23:50:55Z",
+    "nvd_published_at": "2025-06-03T19:15:39Z"
+  }
+}
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