#VU103227 Use of insufficiently random values in undici - CVE-2025-22150

Vulnerability identifier: #VU103227

Vulnerability risk: Medium

CVSSv4.0: 2.7 [CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:L/VI:L/VA:N/SC:N/SI:N/SA:N/E:U/U:Green]

CVE-ID: CVE-2025-22150

CWE-ID: CWE-330

Exploitation vector: Network

Exploit availability: No

Vulnerable software:
undici
Server applications / File servers (FTP/HTTP)

Vendor: Node.js

Description

The vulnerability allows a remote attacker to perform MitM attack.

The vulnerability exists due to the application uses "Math.random()" from the fetch() function to choose the boundary for a "multipart/form-data" request. A remote attacker with ability to intercept traffic can tamper with the requests going to the backend APIs.

Mitigation
Install updates from vendor's website.

Vulnerable software versions

undici: 4.5.0 - 7.2.2

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External links
https://blog.securityevaluators.com/hacking-the-javascript-lottery-80cc437e3b7f
https://github.com/nodejs/undici/blob/8b06b8250907d92fead664b3368f1d2aa27c1f35/lib/web/fetch/body.js#L113
https://github.com/nodejs/undici/commit/711e20772764c29f6622ddc937c63b6eefdf07d0
https://github.com/nodejs/undici/commit/c2d78cd19fe4f4c621424491e26ce299e65e934a
https://github.com/nodejs/undici/commit/c3acc6050b781b827d80c86cbbab34f14458d385
https://github.com/nodejs/undici/security/advisories/GHSA-c76h-2ccp-4975
https://hackerone.com/reports/2913312

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Q & A

Can this vulnerability be exploited remotely?

Yes. This vulnerability can be exploited by a remote non-authenticated attacker via the Internet.

Is there known malware, which exploits this vulnerability?

No. We are not aware of malware exploiting this vulnerability.