{"id":"CVE-2026-42608","summary":"Grav: Unauthenticated Path Traversal & Arbitrary File Write in FormFlash component.","details":"Grav is a file-based Web platform. Prior to 2.0.0-beta.2, there is a Path Traversal vulnerability within the FormFlash core component. By manipulating the session_id (passed as __form-flash-id in POST requests), an unauthenticated attacker can traverse the filesystem to create arbitrary directories and write an index.yaml file containing attacker-controlled data. This vulnerability can lead to unauthorized modification of application behavior, potential data integrity issues, and service disruption in production environments. This vulnerability is fixed in 2.0.0-beta.2.","aliases":["GHSA-hmcx-ch82-3fv2"],"modified":"2026-07-08T08:13:26.637260374Z","published":"2026-05-11T15:02:15.956Z","database_specific":{"cwe_ids":["CWE-22"],"cna_assigner":"GitHub_M","osv_generated_from":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/42xxx/CVE-2026-42608.json"},"references":[{"type":"ADVISORY","url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/42xxx/CVE-2026-42608.json"},{"type":"ADVISORY","url":"https://github.com/getgrav/grav/security/advisories/GHSA-hmcx-ch82-3fv2"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-42608"}],"affected":[{"ranges":[{"type":"GIT","repo":"https://github.com/getgrav/grav","events":[{"introduced":"0"},{"fixed":"3077b04b220318883ed34b6ae2a6cd0f25dba92e"}],"database_specific":{"extracted_events":[{"introduced":"0"},{"fixed":"2.0.0-beta.2"},{"fixed":"2.0.0"}],"cpe":"cpe:2.3:a:getgrav:grav:*:*:*:*:*:*:*:*","source":["AFFECTED_FIELD","CPE_RANGE"]}}],"versions":["2.0.0-beta.1","1.8.0-beta.29","1.8.0-beta.28","1.8.0-beta.27","1.8.0-beta.26","1.8.0-beta.25","1.8.0-beta.24","1.8.0-beta.23","1.8.0-beta.22","1.8.0-beta.21","1.8.0-beta.20","1.8.0-beta.19","1.8.0-beta.18","1.8.0-beta.17","1.8.0-beta.16","1.8.0-beta.15","1.8.0-beta.14","1.8.0-beta.13","1.8.0-beta.12","1.8.0-beta.11","1.8.0-beta.10","1.8.0-beta.9","1.8.0-beta.8","1.8.0-beta.7","1.8.0-beta.6","1.8.0-beta.5","1.8.0-beta.4","1.8.0-beta.3","1.8.0-beta.2","1.8.0-beta.1","1.7.0-rc.20","1.7.0-rc.19","1.7.0-rc.18","1.7.0-rc.17","1.7.0-rc.15","1.7.0-rc.14","1.7.0-rc.13","1.7.0-rc.12","1.7.0-rc.10","1.7.0-rc.9","1.7.0-rc.8","1.7.0-rc.7","1.7.0-rc.6","1.7.0-rc.5","1.7.0-rc.4","1.7.0-rc.3","1.7.0-rc.2","1.7.0-rc.1","1.7.0-beta.10","1.7.0-beta.9","1.7.0-beta.8","1.7.0-beta.7","1.7.0-beta.6","1.7.0-beta.5","1.7.0-beta.4","1.7.0-beta.3","1.7.0-beta.2","1.7.0-beta.1","1.6.0-rc.4","1.6.0-rc.3","1.6.0-rc.2","1.6.0-rc.1","1.6.0-beta.8","1.6.0-beta.7","1.6.0-beta.6","1.6.0-beta.5","1.6.0-beta.2","1.6.0-beta.1","1.5.0-rc.1","1.5.0-beta.2","1.5.0-beta.1","1.3.0-rc.5","1.3.0-rc.4","1.3.0-rc.3","1.3.0-rc.1","1.2.0-rc.3","1.2.0-rc.2","1.2.0-rc.1","1.1.9-rc.3","1.1.9-rc.2","1.1.9-rc.1","1.1.0-rc.3","1.1.0-rc.2","1.1.0-rc.1","1.1.0-beta.5","1.1.0-beta.4","1.1.0-beta.3","1.1.0-beta.2","1.1.0-beta.1","0.9.19","0.9.18","0.9.17","0.9.16","0.9.15","0.9.14","0.9.13","0.9.12","0.9.11","0.9.10","0.9.9","0.9.8","0.9.7","0.9.6","0.9.5","0.9.4","0.9.3","0.9.2","0.9.0","0.8.0"],"database_specific":{"source":"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-42608.json"}}],"schema_version":"1.7.5","severity":[{"type":"CVSS_V4","score":"CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:N/SC:N/SI:N/SA:N/E:P"}]}