GHSA-f269-vfmq-vjvj

Undici: Malicious WebSocket 64-bit length overflows parser and crashes the client

Source: GitHub Advisory Database (reviewed) High CVE-2026-1528

Packages

Ecosystem	Package	Affected	Fixed in
npm	undici	>= 6.0.0, < 6.24.0	6.24.0
npm	undici	>= 7.0.0, < 7.24.0	7.24.0

Details

As written in the advisory (Markdown source, shown as plain text).

### Impact A server can reply with a WebSocket frame using the 64-bit length form and an extremely large length. undici's ByteParser overflows internal math, ends up in an invalid state, and throws a fatal TypeError that terminates the process. ### Patches Patched in the undici version v7.24.0 and v6.24.0. Users should upgrade to this version or later. ### Workarounds There are no workarounds.

References

External links from the advisory. They lead to third-party sites.

https://github.com/nodejs/undici/security/advisories/GHSA-f269-vfmq-vjvj web
https://nvd.nist.gov/vuln/detail/CVE-2026-1528 advisory
https://hackerone.com/reports/3537648 web
https://cna.openjsf.org/security-advisories.html web
https://github.com/nodejs/undici package