CVE-2026-123872: high-severity vulnerability in nodejs node
Node.js is vulnerable to a client certificate authentication bypass via TLS 1.2 renegotiation servername change
Published
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21Vexday Risk Score
No sign of exploitation. No public exploitation artifact known so far.
ssvc Trackcvss 8.1epss 0.4%
A client certificate authentication bypass in Node.js TLS lets a client change the servername during TLS 1.2 renegotiation to reach endpoints it was not authorized for. On a server that applies different client-certificate policies per hostname, for example stricter admin-only client-cert auth on one host and ordinary client-cert auth on another, a client that authenticates for a permitted host can renegotiate the TLS 1.2 connection under a different servername and carry its existing authentication to the protected host, bypassing the stricter policy. This vulnerability affects Node.js 26.x, 24.x, and 22.x.
CVSS:3.0/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:N
Affected products
nodejs · nodeRelated CVEs — nodejs node
In the same product, most dangerous first.