Bug 2560022 (CVE-2026-106072)

Summary:	CVE-2026-106072 nodejs: nodejs: Authentication bypass via non-canonical IPv4 hostname verification
Product:	[Other] Security Response	Reporter:	OSIDB Bzimport <bzimport>
Component:	vulnerability	Assignee:	Product Security DevOps Team <prodsec-dev>
Status:	NEW ---	QA Contact:
Severity:	medium	Docs Contact:
Priority:	medium
Version:	unspecified	CC:	gtanzill, jbuscemi, kaycoth, rhel-process-autobot, watson-tool-maintainers
Target Milestone:	---	Keywords:	Security
Target Release:	---
Hardware:	All
OS:	Linux
Whiteboard:
Fixed In Version:		Doc Type:	---
Doc Text:	A flaw was found in Node.js TLS hostname verification. When a client connects using a non-canonical IPv4 hostname spelling (for example 0177.0.0.1, 0x7f.0.0.1, 2130706433, or 127.1), tls.checkServerIdentity() may fail to classify the host as an IP address, normalize it to a canonical form, and match that form against certificate DNS SANs instead of requiring an IP Address SAN. A certificate that contains a DNS SAN equal to the canonical IP string (for example DNS:127.0.0.1) without a corresponding IP Address SAN can therefore be accepted for an IP endpoint. Exploitation requires a certificate with such a numeric DNS SAN that is trusted by the client, and a platform resolver that accepts the non-canonical spelling (glibc does).	Story Points:	---
Clone Of:		Environment:
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Documentation:	---	CRM:
Verified Versions:		Category:	---
oVirt Team:	---	RHEL 7.3 requirements from Atomic Host:
Cloudforms Team:	---	Target Upstream Version:
Embargoed:
Bug Depends On:	2560611, 2560612, 2560613, 2560614, 2560616, 2560618, 2560620
Bug Blocks:

Description OSIDB Bzimport 2026-10-23 16:23:07 UTC

A flaw in Node.js TLS hostname verification allows a certificate with only a DNS SAN to authenticate an IP endpoint when the client connects using a non-canonical IPv4 spelling, such as `0177.0.0.1`, `0x7f.0.0.1`, `2130706433` or `127.1`.

`tls.checkServerIdentity()` did not classify these hosts as IP addresses, but normalized them to their canonical form and matched the result against the certificate DNS names. A certificate containing `DNS:127.0.0.1` and no `IP Address:127.0.0.1` SAN was therefore accepted, while the same certificate is correctly rejected for `127.0.0.1`. Exploitation requires a certificate with a numeric DNS SAN issued by a CA trusted by the client, and a platform resolver that accepts these spellings, such as glibc.

This vulnerability affects Node.js **26.x**, **24.x**, and **22.x**.

Comment 4 Jon Orris 2026-10-29 14:21:11 UTC

This issue has been addressed in the following products:

  Red Hat Enterprise Linux 8

Via RHSA-2026:92376 https://access.redhat.com/errata/RHSA-2026:92376