{"id":"CVE-2026-34735","summary":"Hytale Modding Vulnerable to Remote Code Execution via File Upload Bypass in `FileController`","details":"The Hytale Modding Wiki is a free service for Hytale mods to host their documentation & wikis. In version 1.2.0 and prior, the quickUpload() endpoint validates uploaded files by checking their MIME type (via PHP's finfo, which inspects file contents) but constructs the stored filename using the client-supplied file extension from getClientOriginalExtension(). These two checks are independent: an attacker can upload a file whose content passes the MIME allowlist while using a .php extension. The file is stored on the public disk and is directly accessible via URL, allowing server-side code execution. At time of publication no known patches exist.","aliases":["GHSA-2xqq-6778-h4j9"],"modified":"2026-07-27T03:56:14.724502669Z","published":"2026-04-02T18:23:26.441Z","database_specific":{"cwe_ids":["CWE-434"],"osv_generated_from":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/34xxx/CVE-2026-34735.json","cna_assigner":"GitHub_M"},"references":[{"type":"ADVISORY","url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/34xxx/CVE-2026-34735.json"},{"type":"ADVISORY","url":"https://github.com/HytaleModding/wiki/security/advisories/GHSA-2xqq-6778-h4j9"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-34735"}],"affected":[{"ranges":[{"type":"GIT","repo":"https://github.com/hytalemodding/wiki","events":[{"introduced":"0"},{"last_affected":"89dfb32585acb1978259287295ddf5ec96e191c3"}],"database_specific":{"source":"AFFECTED_FIELD","extracted_events":[{"introduced":"0"},{"last_affected":"1.2.0"}]}}],"versions":["v1.2.0","v1.1.0","v1.0.0"],"database_specific":{"source":"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-34735.json"}}],"schema_version":"1.7.5","severity":[{"type":"CVSS_V4","score":"CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N"}]}