CVE-2026-123872
Node.js is vulnerable to a client certificate authentication bypass via TLS 1.2 renegotiation servername change
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.
Fixes and workarounds
No remediation reported in collected sources.
Missing remediation information is not evidence that no patch exists.
Affected products and versions
| Product | Versions | Authority |
|---|---|---|
| node nodejs |
≥ 0.0.0; < 22.23.5 (affected, semver) ≥ 23.0.0; < 24.22.3 (affected, semver) ≥ 25.0.0; < 26.13.1 (affected, semver) Other versions: unaffected |
CNA: openjs |
Version ranges are source assertions. Check the vendor advisory and your installed configuration before determining exposure.
CVSS assessments
| Version / score | Vector | Authority |
|---|---|---|
| 3.0 / 8.1 high |
CVSS:3.0/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:N | CNA: openjs |
Exploit evidence
No exploit evidence in collected sources. This is not proof of no exploitation.
References
- https://nodejs.org/en/blog/vulnerability/november-2026-security-releasesCNA: openjs · vendor-advisory
- https://cna.openjsf.org/security-advisories.htmlCNA: openjs
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