CVE-2026-85014Medium· 5.9▾ Sunlitundici'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 wri…
▾ Sunlit zone — Low / medium · no exploitation signal
impact 32.5 · likelihood 0.1 · exploitation 0
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Exploit-prediction probability, daily snapshots since Sep 8.
Disclosure to exploitation, from the record and what we observed since indexing it.
Disclosed via NVD
0.4%
Last analysed / modified upstream
0.4% → 0.5%
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.
undici >= 7.0.0, < 7.29.1undici >= 8.0.0, < 8.10.2Upgrade past the affected range:
undici 8.10.2Affected packages:
undici >= 7.0.0, < 7.29.1undici >= 8.0.0, < 8.10.2Patched in:
undici 7.29.1undici 8.10.2Connected by shared product, vendor, weakness, or advisory.
CVE-2026-19534High· 7.5undici's WebSocket client crashes the whole Node.js process during the opening handshake when a server responds with a subprotocol that the client never requested
CVE-2026-84947Low· 3.7undici's dump interceptor reads and discards a response body up to a configurable maximum size
CVE-2026-85024Medium· 5.9undici bundles a WebSocket client whose permessage-deflate size-limit cleanup removes all listeners from the internal zlib inflate stream, including its error listener, while that stream can still emit
CVE-2026-109855High· 7.5undici is an HTTP client library for Node.js
CVE-2026-84890Medium· 5.9undici's decompress interceptor decompresses response bodies according to the untrusted Content-Encoding header
CVE-2026-18149Medium· 5.9undici's retry handler can leave an already-exposed response body pending forever