Skip to content
CVE PROGRAM SOURCE RECORD5.9 Medium

CVE-2026-85014

undici vulnerable to Denial of Service via WebSocketStream unclean close

Description

undici's experimental WebSocketStream client crashes the whole Node.js process when a remote peer closes the TCP connection without a WebSocket close handshake. On an unclean close the internal socket-close handler calls abort on the writable stream unconditionally and discards the returned promise, but per the WHATWG Streams standard aborting a locked writable returns a promise that rejects with a TypeError. Because the application holds a writer on that writable, which is the only way to write, the rejection is never observed and Node's default unhandled-rejection behavior terminates the process. An untrusted server can therefore crash a client with a single abrupt disconnect, with no authentication and no application mistake. This affects undici versions from 7.0.0 up to 7.29.1 and from 8.0.0 up to 8.10.2. Users should upgrade to undici 7.29.1 or 8.10.2.

Affected products

Version statuses are supplied by the assigning organization. Consult the original record for detailed ranges and platform conditions.

undici undici

Default version status: unaffected

  • 7.0.0 to < 7.29.1affected
  • 7.29.1unaffected
  • 8.0.0 to < 8.10.2affected
  • 8.10.2unaffected
pkg:npm/undici

References