GHSA-5v7r-6r5c-r473
file-type affected by infinite loop in ASF parser on malformed input with zero-size sub-header
At a glance
- Published
- Updated
- CVE
- CVE-2026-31808
- CVSS_V3
- CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L
Description
### Impact A denial of service vulnerability exists in the ASF (WMV/WMA) file type detection parser. When parsing a crafted input where an ASF sub-header has a `size` field of zero, the parser enters an infinite loop. The `payload` value becomes negative (-24), causing `tokenizer.ignore(payload)` to move the read position backwards, so the same sub-header is read repeatedly forever. Any application that uses `file-type` to detect the type of untrusted/attacker-controlled input is affected. An attacker can stall the Node.js event loop with a 55-byte payload. ### Patches Fixed in version 21.3.1. Users should upgrade to >= 21.3.1. ### Workarounds Validate or limit the size of input buffers before passing them to `file-type`, or run file type detection in a worker thread with a timeout. ### References - Fix commit: 319abf871b50ba2fa221b4a7050059f1ae096f4f ### Reporter crnkovic@lokvica.com
Affected packages
| Package | Versions |
|---|---|
| npm · file-type | introduced 13.0.0, fixed 21.3.1 |
References
- https://github.com/sindresorhus/file-type/security/advisories/GHSA-5v7r-6r5c-r473 WEB
- https://nvd.nist.gov/vuln/detail/CVE-2026-31808 ADVISORY
- https://github.com/sindresorhus/file-type/commit/319abf871b50ba2fa221b4a7050059f1ae096f4f WEB
- https://github.com/sindresorhus/file-type PACKAGE
Sources
| Source | Licence |
|---|---|
| OSV.dev | CC-BY 4.0 — GitHub Advisory Database |