CVE-2026-47691: Netty has Insufficient Bailiwick Validation for NS Records
(updated )
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).
References
- access.redhat.com/errata/RHSA-2026:26017
- access.redhat.com/errata/RHSA-2026:26018
- access.redhat.com/errata/RHSA-2026:26586
- access.redhat.com/errata/RHSA-2026:34608
- access.redhat.com/errata/RHSA-2026:37390
- access.redhat.com/security/cve/CVE-2026-47691
- bugzilla.redhat.com/show_bug.cgi?id=2488439
- github.com/advisories/GHSA-5pvg-856g-cp85
- github.com/netty/netty/releases/tag/netty-4.1.135.Final
- github.com/netty/netty/releases/tag/netty-4.2.15.Final
- github.com/netty/netty/security/advisories/GHSA-5pvg-856g-cp85
- nvd.nist.gov/vuln/detail/CVE-2026-47691
- security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-47691.json
Code Behaviors & Features
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