{
  "affected": [
    {
      "ranges": [
        {
          "database_specific": {
            "extracted_events": [
              {
                "introduced": "0"
              },
              {
                "fixed": "7.3.1"
              }
            ],
            "source": [
              "AFFECTED_FIELD",
              "REFERENCES"
            ]
          },
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "1bbdfdeac8e7e91506b1a9271360b9b68d7690d3"
            },
            {
              "fixed": "0f8fb55a7408a92afd34504682a9adc253d34401"
            }
          ],
          "repo": "https://github.com/kunstmaan/kunstmaanbundlescms",
          "type": "GIT"
        }
      ]
    }
  ],
  "aliases": [
    "GHSA-p279-5wcv-45vq"
  ],
  "database_specific": {
    "cna_assigner": "GitHub_M",
    "cwe_ids": [
      "CWE-434"
    ],
    "osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/104xxx/CVE-2026-104890.json"
  },
  "details": "Kunstmaan CMS is an open source content management system based on the Symfony framework. Prior to 7.3.2, src/Kunstmaan/MediaBundle/Helper/File/FileHandler.php performs the blacklisted_extensions check case-sensitively in FileHandler::getFilePath and lowercases the stored extension afterward. An authenticated backend user with media access can upload a mixed-case executable extension such as PHP that bypasses the check and is stored in the web-accessible media directory with an executable lowercase extension. The default blacklist also omits several server-executable extension types, allowing the same code-execution impact where the web server executes uploaded files. This issue is fixed in version 7.3.2.",
  "id": "CVE-2026-104890",
  "modified": "2026-10-07T02:30:32.231129201Z",
  "published": "2026-10-05T15:46:21.959Z",
  "references": [
    {
      "type": "WEB",
      "url": "https://github.com/Kunstmaan/KunstmaanBundlesCMS/releases/tag/7.3.2"
    },
    {
      "type": "ADVISORY",
      "url": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/104xxx/CVE-2026-104890.json"
    },
    {
      "type": "ADVISORY",
      "url": "https://github.com/Kunstmaan/KunstmaanBundlesCMS/security/advisories/GHSA-p279-5wcv-45vq"
    },
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-104890"
    },
    {
      "type": "FIX",
      "url": "https://github.com/Kunstmaan/KunstmaanBundlesCMS/commit/1bbdfdeac8e7e91506b1a9271360b9b68d7690d3"
    }
  ],
  "schema_version": "1.9.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:H",
      "type": "CVSS_V3"
    }
  ],
  "summary": "Kunstmaan CMS: MediaBundle extension blacklist bypass allows authenticated administrators to upload executable PHP files leading to remote code execution"
}