CVE-2026-31808

file-type detects the file type of a file, stream, or data. Prior to 21.3.1, 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. Fixed in version 21.3.1.

CVSS v3 5.3 MEDIUM

5.3^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 3.9 / Impact : 1.4

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact NONE

Integrity Impact NONE

Availability Impact LOW

Scope UNCHANGED

References

Link	Resource
https://github.com/sindresorhus/file-type/commit/319abf871b50ba2fa221b4a7050059f1ae096f4f	Patch
https://github.com/sindresorhus/file-type/security/advisories/GHSA-5v7r-6r5c-r473	Mitigation Patch Vendor Advisory

Configurations

Configuration 1 (hide)

cpe:2.3:a:sindresorhus:file-type:*:*:*:*:*:node.js:*:*

History

No history.

Information

Published : 2026-03-10 21:16

Updated : 2026-03-18 19:48

NVD link : CVE-2026-31808

Mitre link : CVE-2026-31808

CVE.ORG link : CVE-2026-31808

JSON object : View

Products Affected

sindresorhus

file-type

CWE

CWE-835

Loop with Unreachable Exit Condition ('Infinite Loop')

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