CVE-2026-34735 (GCVE-0-2026-34735)

Vulnerability from cvelistv5 – Published: 2026-04-02 18:23 – Updated: 2026-04-02 19:14
VLAI
Title
Hytale Modding Vulnerable to Remote Code Execution via File Upload Bypass in `FileController`
Summary
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.
Severity
8.7 (High)
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
SSVC
Exploitation: poc Automatable: no Technical Impact: total
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-04-02 19:13 UTC
CWE
  • CWE-434 - Unrestricted Upload of File with Dangerous Type
Assigner
GitHub_M CNA
References
Impacted products
Vendor Product Version
HytaleModding wiki Affected: <= 1.2.0
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