{
  "affected": [
    {
      "ranges": [
        {
          "database_specific": {
            "extracted_events": [
              {
                "introduced": "0"
              },
              {
                "fixed": "2.0.14"
              }
            ],
            "source": [
              "AFFECTED_FIELD",
              "DESCRIPTION"
            ]
          },
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "5192316f5bf0f033636f43561829d7fc13a4ab64"
            }
          ],
          "repo": "https://github.com/getgrav/grav",
          "type": "GIT"
        }
      ]
    }
  ],
  "aliases": [
    "GHSA-q2j8-x8hf-63ch"
  ],
  "database_specific": {
    "cna_assigner": "VulnCheck",
    "cwe_ids": [
      "CWE-79"
    ],
    "osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/75xxx/CVE-2026-75834.json"
  },
  "details": "Grav before 2.0.14 contains a stored cross-site scripting vulnerability in the Security::detectXss() function (system/src/Grav/Common/Security.php). All XSS detection patterns use the PCRE /u (UTF-8) modifier, so a single invalid UTF-8 byte anywhere in page content causes preg_match() to return false for every pattern, silently bypassing the save-time XSS safety gate (Validation::checkSafety()). An authenticated attacker with page-edit permissions (without the security.xss_whitelist privilege) can store malicious JavaScript that executes in the browser of a visitor who views the affected page.",
  "id": "CVE-2026-75834",
  "modified": "2026-09-10T03:31:06.263533689Z",
  "published": "2026-08-18T11:19:45.094Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/75xxx/CVE-2026-75834.json"
    },
    {
      "type": "ADVISORY",
      "url": "https://github.com/getgrav/grav/security/advisories/GHSA-q2j8-x8hf-63ch"
    },
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-75834"
    },
    {
      "type": "ADVISORY",
      "url": "https://www.vulncheck.com/advisories/grav-before-stored-xss-via-invalid-utf-8-byte"
    }
  ],
  "schema_version": "1.9.0",
  "severity": [
    {
      "score": "CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:P/VC:N/VI:N/VA:N/SC:L/SI:L/SA:N",
      "type": "CVSS_V4"
    }
  ],
  "summary": "Grav before 2.0.14 Stored XSS via Invalid UTF-8 Byte"
}