{
  "affected": [
    {
      "ranges": [
        {
          "database_specific": {
            "extracted_events": [
              {
                "introduced": "4.0.0"
              },
              {
                "fixed": "5.3.50"
              },
              {
                "introduced": "5.4.0-RC1"
              },
              {
                "fixed": "5.7.12"
              }
            ],
            "source": [
              "AFFECTED_FIELD",
              "REFERENCES"
            ]
          },
          "events": [
            {
              "introduced": "84b2fe637d5ead531f117f26b48d1b9de8df4074"
            },
            {
              "introduced": "c5e3841e5107ab36ae2bf7795fb8d51d3d30f88b"
            },
            {
              "fixed": "a11109b60dedcbd99e32a4e8550afdadb500f2c5"
            },
            {
              "fixed": "a6543f49a92187a7368f51b290179c4795386e23"
            },
            {
              "fixed": "34dd27ee6739f10568d3d95d8784862255c925b4"
            }
          ],
          "repo": "https://github.com/contao/contao",
          "type": "GIT"
        }
      ]
    }
  ],
  "aliases": [
    "GHSA-9ff2-p842-45wq"
  ],
  "database_specific": {
    "cna_assigner": "GitHub_M",
    "cwe_ids": [
      "CWE-352"
    ],
    "osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/107xxx/CVE-2026-107848.json"
  },
  "details": "Contao is an Open Source CMS. From version 4.0.0 until 5.3.50 and 5.7.12, RequestTokenListener validates REQUEST_TOKEN only for POST requests, while the declarative GET guard runs only when an act parameter is present. Backend actions dispatched through the key parameter can therefore execute without a CSRF token when an authenticated backend user loads an attacker-controlled URL. Reachable actions remain limited to modules available to that user, and the advisory demonstrates destructive or state-changing actions rather than privilege escalation. This issue is fixed in versions 5.3.50 and 5.7.12.",
  "id": "CVE-2026-107848",
  "modified": "2026-10-11T02:30:22.279767367Z",
  "published": "2026-10-09T20:22:12.778Z",
  "references": [
    {
      "type": "WEB",
      "url": "https://github.com/contao/contao/releases/tag/5.7.12"
    },
    {
      "type": "ADVISORY",
      "url": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/107xxx/CVE-2026-107848.json"
    },
    {
      "type": "ADVISORY",
      "url": "https://github.com/contao/contao/security/advisories/GHSA-9ff2-p842-45wq"
    },
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-107848"
    },
    {
      "type": "FIX",
      "url": "https://github.com/contao/contao/commit/34dd27ee6739f10568d3d95d8784862255c925b4"
    }
  ],
  "schema_version": "1.9.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:U/C:N/I:L/A:N",
      "type": "CVSS_V3"
    }
  ],
  "summary": "Contao: Cross-site request forgery in custom backend actions"
}