CVE-2026-85014 · GHSA-rx4f-c7p8-82vq
undici vulnerable to Denial of Service via WebSocketStream unclean close
- Risk score
- 46/100
- CVSS
- 5.9 v3.1
- Exploit chance (30 days)
- 0.4%
- Published
- 29 Sep 2026
Open in the live forecast Today's forecast
What to know
- What it is
- undici's WebSocketStream crashes the client process when a WebSocket connection is closed abruptly without a close handshake. On such an unclean close, the internal socket-close handler calls abort() on the writable stream even when the application holds a writer lock. Per the WHATWG Streams standard, aborting a locke…
- Affected
- undici (npm) >= 7.0.0, < 7.29.1; undici (npm) >= 8.0.0, < 8.10.2
- Fix
- Upgrade undici to 7.29.1 or 8.10.2 (whichever matches your release line) or later.
- Exploitation
- No known exploitation
Why it is Yellow
- CVSS 5.9 medium
- On your watchlist: npm
Affected packages
| Package | Ecosystem | Vulnerable | Fixed in |
|---|---|---|---|
| undici | npm | >= 7.0.0, < 7.29.1 | 7.29.1 |
| undici | npm | >= 8.0.0, < 8.10.2 | 8.10.2 |
References
- https://github.com/advisories/GHSA-rx4f-c7p8-82vq
- https://github.com/nodejs/undici/security/advisories/GHSA-rx4f-c7p8-82vq
- https://nvd.nist.gov/vuln/detail/CVE-2026-85014
- https://github.com/nodejs/undici/commit/1858656ebb1e919311c1f31613dfd581b7214349
- https://github.com/nodejs/undici/commit/662d0ea671fe64139e79533c913fce412765e1d7
- https://cna.openjsf.org/security-advisories.html
- https://github.com/nodejs/undici/releases/tag/v7.29.1
- https://github.com/nodejs/undici/releases/tag/v8.10.2
- https://github.com/advisories/GHSA-rx4f-c7p8-82vq
Original description
## Impact undici's `WebSocketStream` crashes the client process when a WebSocket connection is closed abruptly without a close handshake. On such an unclean close, the internal socket-close handler calls `abort()` on the writable stream even when the application holds a writer lock. Per the WHATWG Streams standard, aborting a locked stream returns a promise that rejects with a `TypeError`, and the handler discards that promise. The unobserved rejection surfaces as an `unhandledRejection` and, under Node.js's default behavior, terminates the process. A malicious or compromised WebSocket server can crash a client with a single connection teardown (a TCP reset, a proxy teardown, or a protocol-violating frame). Affected applications are those using the `WebSocketStream` API and writing through a writer, which is the standard way to write. All releases from undici 7.0.0 are affected. WebSocketStream was introduced in 7.0.0. ## Patches Upgrade to undici v7.29.1 or v8.10.2. ## Workarounds No workaround is available.
Last activity 29 Sep 2026. Patch Forecast updates every hour.