{"id":"CVE-2025-66305","aliases":["GHSA-m8vh-v6r6-w7p6"],"url":"https://o3.security/vulnerability/CVE-2025-66305","summary":"Grav vulnerable to Denial of Service via Improper Input Handling in 'Supported' Parameter","details":"Grav is a file-based Web platform. Prior to 1.8.0-beta.27, a Denial of Service (DoS) vulnerability was identified in the \"Languages\" submenu of the Grav admin configuration panel (/admin/config/system). Specifically, the Supported parameter fails to properly validate user input. If a malformed value is inserted—such as a single forward slash (/) or an XSS test string—it causes a fatal regular expression parsing error on the server. This leads to application-wide failure due to the use of the preg_match() function with an improperly constructed regular expression, resulting in an error. Once triggered, the site becomes completely unavailable to all users. This vulnerability is fixed in 1.8.0-beta.27.","published":"2025-12-01T21:43:29.725Z","modified":"2026-08-08T03:48:16.026595271Z","cvss":null,"epss":null,"cisaKev":null,"exploitsKnown":0,"affectedPackages":[{"ecosystem":"Packagist","name":"getgrav/grav","fixedVersion":"1.8.0-beta.27"}],"fix":{"url":"https://github.com/getgrav/grav/commit/ed640a13143c4177af013cf001969ed2c5e197ee","label":"getgrav/grav@ed640a1"},"references":[{"type":"ADVISORY","url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2025/66xxx/CVE-2025-66305.json"},{"type":"ADVISORY","url":"https://github.com/getgrav/grav/security/advisories/GHSA-m8vh-v6r6-w7p6"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2025-66305"},{"type":"FIX","url":"https://github.com/getgrav/grav/commit/ed640a13143c4177af013cf001969ed2c5e197ee"}],"provenance":{"sources":["OSV.dev","FIRST.org (EPSS)"],"lastVerified":"2026-08-08T03:48:16.026595271Z"}}