# CVE-2026-47691: Netty has Insufficient Bailiwick Validation for NS Records

> CVE-2026-47691: Netty has Insufficient Bailiwick Validation for NS Records. CVSS 8.7 (CVSS 3.1).

Canonical: https://rewindex.com/cve/CVE-2026-47691
Last updated: 2026-09-18T13:18:28Z

- Published: 2026-06-12 14:33 UTC · Updated: 2026-09-18 13:18 UTC · Assigner: GitHub\_M
- CVSS: 8.7 (CVSS 3.1) · Severity: High · Vector: CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:C/C:H/I:H/A:N
- EPSS: 0.37%, 31th percentile (scored 2026-10-25)
- CISA KEV: no
- CWE: CWE-345

## 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.

## Affected vendors and products

- netty: netty
- Red Hat: Red Hat Build of Apache Camel 3.33 for Quarkus 3.33.2.SP1
- Red Hat: Red Hat build of Apache Camel 4.18.1.P1 for Spring Boot 3.5.16
- Red Hat: Red Hat build of Apache Camel 4 for Quarkus 3
- Red Hat: Red Hat build of Apache Camel - HawtIO 4
- Red Hat: Red Hat build of Apicurio Registry 3
- Red Hat: Red Hat build of Debezium 3
- Red Hat: Red Hat Build of Keycloak
- Red Hat: Red Hat Data Grid 8.6.2
- Red Hat: Red Hat Enterprise Linux AI (RHEL AI) 3
- Red Hat: Red Hat JBoss Enterprise Application Platform 7.4 ELS on RHEL 7
- Red Hat: Red Hat JBoss Enterprise Application Platform 7.4 ELS on RHEL 8
- Red Hat: Red Hat JBoss Enterprise Application Platform 8.1.7.GA
- Red Hat: Red Hat JBoss Enterprise Application Platform 8.1 for RHEL 10
- Red Hat: Red Hat JBoss Enterprise Application Platform 8.1 for RHEL 8
- Red Hat: Red Hat JBoss Enterprise Application Platform 8.1 for RHEL 9
- Red Hat: Streams for Apache Kafka 2.9.4
- Red Hat: Streams for Apache Kafka 3.2.1

## Tracked companies

- [Confluence](https://rewindex.com/company/confluence.md)

## References

- [CVE record on cve.org](https://www.cve.org/CVERecord?id=CVE-2026-47691)
- [NVD entry](https://nvd.nist.gov/vuln/detail/CVE-2026-47691)
- [https://github.com/netty/netty/releases/tag/netty-4.1.135.Final](https://github.com/netty/netty/releases/tag/netty-4.1.135.Final)
- [https://github.com/netty/netty/releases/tag/netty-4.2.15.Final](https://github.com/netty/netty/releases/tag/netty-4.2.15.Final)
- [https://github.com/netty/netty/security/advisories/GHSA-5pvg-856g-cp85](https://github.com/netty/netty/security/advisories/GHSA-5pvg-856g-cp85)

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_Sources: CVE records from the CVE Program (cve.org). CVE® is a registered trademark of The MITRE Corporation. (https://www.cve.org/) This product uses data from the NVD API but is not endorsed or certified by the NVD. (https://nvd.nist.gov/) Known Exploited Vulnerabilities catalog from CISA. (https://www.cisa.gov/known-exploited-vulnerabilities-catalog) EPSS scores from FIRST (Exploit Prediction Scoring System). (https://www.first.org/epss/)_


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Canonical: https://rewindex.com/cve/CVE-2026-47691 · Markdown: https://rewindex.com/cve/CVE-2026-47691.md · JSON: https://rewindex.com/api/v1/cves/CVE-2026-47691 · Data licensed CC BY 4.0 (https://creativecommons.org/licenses/by/4.0/) · Generated 2026-10-26T03:12:30.003Z