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National Vulnerability Database

National Vulnerability Database

NVD

National Vulnerability Database
  1. Vulnerabilities

CVE-2026-47691 Detail

Description

Netty is a network application framework for development of protocol servers and clients. Prior to versions 4.1.135.Final and 4.2.15.Final, Netty's `DnsResolveContext` insufficiently validates the bailiwick of NS records, enabling DNS Cache Poisoning. An attacker controlling an authoritative name server for a subdomain can poison the cache for parent domains (like `.co.uk`). In `io.netty.resolver.dns.DnsResolveContext.AuthoritativeNameServerList#add` method accepts any NS record from the AUTHORITY section as long as the record's name is a suffix of the questionName. Subsequently, the `handleWithAdditional` method caches the associated A records from the ADDITIONAL section directly into the `authoritativeDnsServerCache` under the parent domain's key. This bypasses standard bailiwick rules, where a server authoritative for a subdomain should not be trusted to provide authoritative records for its parent. The poisoned cache is then used for all future resolutions under the parent domain's key. Versions 4.1.135.Final and 4.2.15.Final patch the issue.


Metrics

 
NVD enrichment efforts reference publicly available information to associate vector strings. CVSS information contributed by other sources is also displayed.
CVSS 4.0 Severity and Vector Strings:

NIST CVSS score
NIST: NVD
N/A
NVD assessment not yet provided.

References to Advisories, Solutions, and Tools

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URL Source(s) Tag(s)
https://github.com/netty/netty/releases/tag/netty-4.1.135.Final GitHub, Inc. Release Notes 
https://github.com/netty/netty/releases/tag/netty-4.2.15.Final GitHub, Inc. Release Notes 
https://github.com/netty/netty/security/advisories/GHSA-5pvg-856g-cp85 GitHub, Inc. Vendor Advisory 

Weakness Enumeration

CWE-ID CWE Name Source
CWE-345 Insufficient Verification of Data Authenticity GitHub, Inc.  

Known Affected Software Configurations Switch to CPE 2.2

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Change History

2 change records found show changes

Quick Info

CVE Dictionary Entry:
CVE-2026-47691
NVD Published Date:
06/12/2026
NVD Last Modified:
06/14/2026
Source:
GitHub, Inc.