CVE-2025-22150

MEDIUM6.8EPSS 0.60%

Use of Insufficiently Random Values in undici

Published: 1/21/2025Modified: 2/4/2026
Also known as:GHSA-c76h-2ccp-4975ALPINE-CVE-2025-22150CGA-gjjv-rj3w-cwpq

Description

### Impact [Undici `fetch()` uses Math.random()](https://github.com/nodejs/undici/blob/8b06b8250907d92fead664b3368f1d2aa27c1f35/lib/web/fetch/body.js#L113) to choose the boundary for a multipart/form-data request. It is known that the output of Math.random() can be predicted if several of its generated values are known. If there is a mechanism in an app that sends multipart requests to an attacker-controlled website, they can use this to leak the necessary values. Therefore, An attacker can tamper with the requests going to the backend APIs if certain conditions are met. ### Patches This is fixed in 5.28.5; 6.21.1; 7.2.3. ### Workarounds Do not issue multipart requests to attacker controlled servers. ### References * https://hackerone.com/reports/2913312 * https://blog.securityevaluators.com/hacking-the-javascript-lottery-80cc437e3b7f

Affected packages (3)

CVSS scores

SourceVersionSeverityVector
osvCVSS 3.1MEDIUM6.8CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:H/I:H/A:N

References (11)