CVE-2026-105483: A flaw in Node.js TLS hostname verification allows a certificate without a matching IP address SAN to authenticate a connection to an IPv4 address when the host is written with non-ASCII characters, such as fullwidth digits (`127.0.0.1`). `tls.checkServerIdentity()` did not recognize such hosts as IP addresses, even though they normalize and resolve to a regular IPv4 address, and matched them against the certificate DNS names and Common Name instead. A certificate containing `DNS:127.0.0.1` or `DNS:*.0.0.1` could therefore be accepted for an IP endpoint it was not issued for. This is a regression introduced after the fix for CVE-2026-48618. This vulnerability affects Node.js **26.x** and **24.x**.

Overview

Severity
High (CVSS 7.4)
CVSS Vector
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:N
Exploit Status
Not Exploited
Patch Tuesday
2026-Oct
Released
2026-10-25
Last Updated
2026-10-26
EPSS Score
0.27% (percentile: 19.8%)

Detection & Weaponization (1 sources)

Maturity: Exploit

  • GitHub PoC: 1 repositories

Affected Products (1)

Open Source Software

  • azl3 nodejs 24.21.0-1 on Azure Linux 3.0

Revision History

  • 2026-10-25: Information published.
  • 2026-10-26: Information published.