Uncaught Exception Affecting undici package, versions >=4.2.1 <6.29.1>=7.0.0 <7.30.1>=8.0.0 <8.12.2


Severity

Recommended
0.0
high
0
10

CVSS assessment by Snyk's Security Team. Learn more

Threat Intelligence

EPSS
0.18% (8th percentile)

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  • Snyk IDSNYK-JS-UNDICI-21181013
  • published18 Oct 2026
  • disclosed15 Oct 2026
  • creditbenzdeus

Introduced: 15 Oct 2026

NewCVE-2026-87018  (opens in a new tab)
CWE-248  (opens in a new tab)

How to fix?

Upgrade undici to version 6.29.1, 7.30.1, 8.12.2 or higher.

Overview

undici is an An HTTP/1.1 client, written from scratch for Node.js

Affected versions of this package are vulnerable to Uncaught Exception via unhandled ERR_TLS_CERT_ALTNAME_INVALID errors in onHttpSocketError, onHttp2SessionError, and onHttp2SocketError. When a TLS connection is established and the server's certificate fails Subject Alternative Name validation post-connect, the error propagates and triggers a failed assert call, crashing the process. An attacker who can cause the client to connect to a server presenting an invalid TLS certificate can exploit this to crash the Node.js process.

CVSS Base Scores

version 4.0
version 3.1