{"id":"CVE-2026-47691","title":"Netty is a network application framework for development of protocol servers and clients","summary":"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 Ca…","severity":"high","cvss":8.7,"cvssVector":"CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:C/C:H/I:H/A:N","cwe":["CWE-345","CWE-346"],"vendor":"netty","product":"netty","affected":["netty < 4.1.135","netty >= 4.2.0, < 4.2.15"],"patched":["netty 4.2.15"],"published":"2026-06-12","updated":"2026-09-18","sourceUpdated":"2026-09-18T13:18:28.497","source":"NVD","sourceUrl":"https://nvd.nist.gov/vuln/detail/CVE-2026-47691","references":[{"url":"https://github.com/netty/netty/releases/tag/netty-4.1.135.Final","label":"security-advisories@github.com"},{"url":"https://github.com/netty/netty/releases/tag/netty-4.2.15.Final","label":"security-advisories@github.com"},{"url":"https://github.com/netty/netty/security/advisories/GHSA-5pvg-856g-cp85","label":"security-advisories@github.com"},{"url":"https://access.redhat.com/errata/RHSA-2026:26017","label":"0b0ca135-0b70-47e7-9f44-1890c2a1c46c"},{"url":"https://access.redhat.com/errata/RHSA-2026:26018","label":"0b0ca135-0b70-47e7-9f44-1890c2a1c46c"},{"url":"https://access.redhat.com/errata/RHSA-2026:26586","label":"0b0ca135-0b70-47e7-9f44-1890c2a1c46c"},{"url":"https://access.redhat.com/errata/RHSA-2026:34608","label":"0b0ca135-0b70-47e7-9f44-1890c2a1c46c"},{"url":"https://access.redhat.com/errata/RHSA-2026:37390","label":"0b0ca135-0b70-47e7-9f44-1890c2a1c46c"},{"url":"https://access.redhat.com/errata/RHSA-2026:41951","label":"0b0ca135-0b70-47e7-9f44-1890c2a1c46c"},{"url":"https://access.redhat.com/errata/RHSA-2026:48151","label":"0b0ca135-0b70-47e7-9f44-1890c2a1c46c"},{"url":"https://access.redhat.com/errata/RHSA-2026:49700","label":"0b0ca135-0b70-47e7-9f44-1890c2a1c46c"},{"url":"https://access.redhat.com/errata/RHSA-2026:49701","label":"0b0ca135-0b70-47e7-9f44-1890c2a1c46c"},{"url":"https://access.redhat.com/errata/RHSA-2026:50085","label":"0b0ca135-0b70-47e7-9f44-1890c2a1c46c"},{"url":"https://access.redhat.com/errata/RHSA-2026:53644","label":"0b0ca135-0b70-47e7-9f44-1890c2a1c46c"},{"url":"https://access.redhat.com/errata/RHSA-2026:53645","label":"0b0ca135-0b70-47e7-9f44-1890c2a1c46c"},{"url":"https://access.redhat.com/errata/RHSA-2026:53646","label":"0b0ca135-0b70-47e7-9f44-1890c2a1c46c"},{"url":"https://access.redhat.com/errata/RHSA-2026:54435","label":"0b0ca135-0b70-47e7-9f44-1890c2a1c46c"},{"url":"https://access.redhat.com/errata/RHSA-2026:62260","label":"0b0ca135-0b70-47e7-9f44-1890c2a1c46c"},{"url":"https://access.redhat.com/errata/RHSA-2026:65126","label":"0b0ca135-0b70-47e7-9f44-1890c2a1c46c"},{"url":"https://access.redhat.com/security/cve/CVE-2026-47691","label":"0b0ca135-0b70-47e7-9f44-1890c2a1c46c"},{"url":"https://bugzilla.redhat.com/show_bug.cgi?id=2488439","label":"0b0ca135-0b70-47e7-9f44-1890c2a1c46c"},{"url":"https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-47691.json","label":"0b0ca135-0b70-47e7-9f44-1890c2a1c46c"},{"url":"https://access.redhat.com/errata/RHSA-2026:53806","label":"0b0ca135-0b70-47e7-9f44-1890c2a1c46c"},{"url":"https://www.cve.org/CVERecord?id=CVE-2026-47691"},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2026-47691"},{"url":"https://github.com/advisories/GHSA-5pvg-856g-cp85"}],"tags":["nvd","cve.org","csaf","vex","red-hat","ghsa","maven"],"epss":0.00386,"epssPercentile":0.32442,"aliases":["GHSA-5pvg-856g-cp85"],"ecosystem":"maven","ssvc":{"exploitation":"none","automatable":"no","technicalImpact":"total","timestamp":"2026-06-12T00:00:00+00:00"},"ingestedAt":"2026-07-03T14:03:37.097Z","slug":"CVE-2026-47691","body":"## Overview\n\nNetty 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.\n\n## Affected\n\n- `netty < 4.1.135`\n- `netty >= 4.2.0, < 4.2.15`\n\n## Remediation\n\nUpgrade past the affected range:\n\n- `netty 4.2.15`\n\n## Package advisory (CVE-2026-47691)\n\nAffected packages:\n\n- `io.netty:netty-resolver-dns >= 4.2.0.Final, <= 4.2.14.Final`\n- `io.netty:netty-resolver-dns <= 4.1.134.Final`\n\nPatched in:\n\n- `io.netty:netty-resolver-dns 4.2.15.Final`\n- `io.netty:netty-resolver-dns 4.1.135.Final`\n\nSource: https://github.com/advisories/GHSA-5pvg-856g-cp85\n\n## Vendor advisories\n\n- **RHSA-2026:49700** · Red Hat · fixed in: Red Hat JBoss EAP 8.1 for RHEL 10, Red Hat JBoss EAP 8.1 for RHEL 8, Red Hat JBoss EAP 8.1 for RHEL 9 · released 2026-08-03 · [advisory](https://access.redhat.com/errata/RHSA-2026:49700)\n- **RHSA-2026:53644** · Red Hat · fixed in: Red Hat JBoss EAP 7.4 ELS for RHEL 7 Server · released 2026-08-11 · [advisory](https://access.redhat.com/errata/RHSA-2026:53644)\n- **RHSA-2026:48151** · Red Hat · fixed in: Cryostat 4 on RHEL 9 · released 2026-07-29 · [advisory](https://access.redhat.com/errata/RHSA-2026:48151)\n- **RHSA-2026:26586** · Red Hat · fixed in: Red Hat Build of Apache Camel 3.33 for Quarkus 3.33.2.SP1 · released 2026-06-17 · [advisory](https://access.redhat.com/errata/RHSA-2026:26586)\n- **RHSA-2026:41951** · Red Hat · fixed in: Red Hat Data Grid 8.6.2 · released 2026-07-20 · [advisory](https://access.redhat.com/errata/RHSA-2026:41951)\n- **RHSA-2026:53806** · Red Hat · fixed in: Red Hat JBoss Enterprise Application Platform 7.4.25 · released 2026-08-11 · [advisory](https://access.redhat.com/errata/RHSA-2026:53806)\n- **RHSA-2026:50085** · Red Hat · fixed in: Red Hat JBoss Enterprise Application Platform 8.1 · released 2026-08-04 · [advisory](https://access.redhat.com/errata/RHSA-2026:50085)\n- **RHSA-2026:49701** · Red Hat · fixed in: Red Hat JBoss Enterprise Application Platform 8.1.7.GA · released 2026-08-03 · [advisory](https://access.redhat.com/errata/RHSA-2026:49701)\n- **RHSA-2026:62260** · Red Hat · fixed in: Red Hat OpenShift Dev Spaces 3.30 · released 2026-09-01 · [advisory](https://access.redhat.com/errata/RHSA-2026:62260)\n- **RHSA-2026:37390** · Red Hat · fixed in: Red Hat build of Apache Camel 4.18.1.P1 for Spring Boot 3.5.16 · released 2026-07-09 · [advisory](https://access.redhat.com/errata/RHSA-2026:37390)\n- **RHSA-2026:26018** · Red Hat · fixed in: Red Hat build of Quarkus 3.27.4.SP1 · released 2026-06-17 · [advisory](https://access.redhat.com/errata/RHSA-2026:26018)\n- **Red Hat VEX** · Important · affected: OpenShift Serverless, Red Hat build of Apache Camel - HawtIO 4, Red Hat build of Apache Camel 4 for Quarkus 3, Red Hat build of Apicurio Registry 3, Red Hat build of Debezium 3, Red Hat Fuse 7, … · no fix planned: Red Hat build of Debezium 3, Red Hat Fuse 7, OpenShift Serverless, Red Hat build of Apache Camel - HawtIO 4, … · updated 2026-09-17 · [vex](https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-47691.json)\n- **RHSA-2026:65126** · Red Hat · fixed in: Red Hat OpenShift AI 2.25 · released 2026-09-08 · [advisory](https://access.redhat.com/errata/RHSA-2026:65126)\n- **RHSA-2026:53645** · Red Hat · fixed in: Red Hat JBoss EAP 7.4 ELS for RHEL 8 · released 2026-08-11 · [advisory](https://access.redhat.com/errata/RHSA-2026:53645)\n- **RHSA-2026:53646** · Red Hat · fixed in: Red Hat JBoss EAP 7.4 ELS for RHEL 9 · released 2026-08-11 · [advisory](https://access.redhat.com/errata/RHSA-2026:53646)","depth":"twilight","depthScore":48,"depthScoreParts":{"impact":47.8,"likelihood":0.1,"exploitation":0,"ransomware":0},"changes":[]}