Bug 2559875 (CVE-2026-105482)

Summary:	CVE-2026-105482 nodejs: nodejs: dns.resolve truncates hostnames containing a NUL character
Product:	[Other] Security Response	Reporter:	OSIDB Bzimport <bzimport>
Component:	vulnerability	Assignee:	Product Security <prodsec-ir-bot>
Status:	NEW ---	QA Contact:
Severity:	high	Docs Contact:
Priority:	high
Version:	unspecified	CC:	akito5623, aruffin, 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 the Node.js DNS resolver APIs. Hostnames passed to dns.resolve that contain an embedded NUL character can be truncated when processed by c-ares. An attacker who can supply such a name may cause the application to resolve and act on an unintended hostname.	Story Points:	---
Clone Of:		Environment:
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Regression:	---	Mount Type:	---
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oVirt Team:	---	RHEL 7.3 requirements from Atomic Host:
Cloudforms Team:	---	Target Upstream Version:
Embargoed:
Bug Depends On:	2559941, 2559944, 2559949, 2559957, 2559942, 2559952, 2559955
Bug Blocks:

Description OSIDB Bzimport 2026-10-23 14:11:19 UTC

A flaw was found in Node.js. The callback- and promise-based dns.resolve APIs did not reject hostnames containing an embedded NUL character. Because c-ares treats the name as a C string, a name such as example.com\0.trusted.corp is truncated to example.com, so the resolver returns records for an unintended hostname.

Comment 2 Akiyoshi Kurita 2026-10-28 18:01:43 UTC

Hello Red Hat Product Security team,

A public proof of concept (PoC) has been reported for CVE-2026-105482, a Node.js DNS hostname truncation issue involving embedded NUL bytes.

PoC reference:
https://github.com/CaterMaoZi/CVE-2026-105482-POC

According to the report, dns.resolve*() may resolve a different hostname from the one validated by an application, potentially bypassing domain allowlist checks. This issue has been described as an incomplete fix for CVE-2026-48930.

I have not independently reproduced the PoC on RHEL. I am sharing the reference for your awareness and impact assessment.

Thank you.

Comment 3 Jon Orris 2026-10-29 14:21:02 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

Comment 4 Jon Orris 2026-10-29 22:29:53 UTC

This issue has been addressed in the following products:

  Red Hat Enterprise Linux 9

Via RHSA-2026:92378 https://access.redhat.com/errata/RHSA-2026:92378