{"id":"CVE-2026-44249","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. In netty-handler prior to versions 4.1.135.Final and 4.2.15.Final, an attacker can bypass IPv6 subnet rules due to an incorrect masking operation i…","severity":"high","cvss":8.1,"cvssVector":"CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H","cwe":["CWE-284","CWE-697","CWE-1287"],"vendor":"netty","product":"netty","affected":["netty < 4.1.135","netty >= 4.2.0, < 4.2.15"],"patched":["netty 4.2.15"],"published":"2026-06-11","updated":"2026-09-18","sourceUpdated":"2026-09-18T13:18:23.463","source":"NVD","sourceUrl":"https://nvd.nist.gov/vuln/detail/CVE-2026-44249","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-3qp7-7mw8-wx86","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-2026:28573","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-2026:36820","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-2026:48124","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-2026:65126","label":"0b0ca135-0b70-47e7-9f44-1890c2a1c46c"},{"url":"https://access.redhat.com/errata/RHSA-2026:66488","label":"0b0ca135-0b70-47e7-9f44-1890c2a1c46c"},{"url":"https://access.redhat.com/errata/RHSA-2026:66545","label":"0b0ca135-0b70-47e7-9f44-1890c2a1c46c"},{"url":"https://access.redhat.com/security/cve/CVE-2026-44249","label":"0b0ca135-0b70-47e7-9f44-1890c2a1c46c"},{"url":"https://bugzilla.redhat.com/show_bug.cgi?id=2488081","label":"0b0ca135-0b70-47e7-9f44-1890c2a1c46c"},{"url":"https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-44249.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-2026-44249"},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2026-44249"},{"url":"https://access.redhat.com/errata/RHSA-2026:69459"}],"tags":["nvd","cve.org","csaf","vex","red-hat"],"epss":0.01025,"epssPercentile":0.61564,"ssvc":{"exploitation":"none","automatable":"no","technicalImpact":"total","timestamp":"2026-06-12T00:00:00+00:00"},"ingestedAt":"2026-07-03T14:03:37.088Z","slug":"CVE-2026-44249","body":"## Overview\n\nNetty is a network application framework for development of protocol servers and clients. In netty-handler prior to versions 4.1.135.Final and 4.2.15.Final, an attacker can bypass IPv6 subnet rules due to an incorrect masking operation in IpSubnetFilterRule.compareTo(). Valid public IP addresses can bypass the restrictions. 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## 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-2026:28573** · Red Hat · fixed in: Red Hat Offline Knowledge Portal 1.2.4 · released 2026-06-23 · [advisory](https://access.redhat.com/errata/RHSA-2026:28573)\n- **RHSA-2026:48124** · Red Hat · fixed in: Red Hat OpenShift Dev Spaces 3.29 · released 2026-07-29 · [advisory](https://access.redhat.com/errata/RHSA-2026:48124)\n- **RHSA-2026:36820** · Red Hat · fixed in: Red Hat OpenShift Dev Spaces 3.29 · released 2026-07-08 · [advisory](https://access.redhat.com/errata/RHSA-2026:36820)\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 Build of Keycloak, … · no fix planned: Red Hat build of Debezium 3, Red Hat Enterprise Linux AI (RHEL AI) 3, Red Hat Fuse 7, OpenShift Serverless, … · updated 2026-09-21 · [vex](https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-44249.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-2026:66545** · Red Hat · fixed in: Red Hat AMQ Broker 7.13.6 · released 2026-09-10 · [advisory](https://access.redhat.com/errata/RHSA-2026:66545)\n- **RHSA-2026:66488** · Red Hat · fixed in: Red Hat AMQ Broker 7.14.1 · released 2026-09-10 · [advisory](https://access.redhat.com/errata/RHSA-2026:66488)\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)\n- **RHSA-2026:69459** · Red Hat · fixed in: AMQ Clients 2026.Q3 · released 2026-09-21 · [advisory](https://access.redhat.com/errata/RHSA-2026:69459)","depth":"twilight","depthScore":45,"depthScoreParts":{"impact":44.6,"likelihood":0.2,"exploitation":0,"ransomware":0},"changes":[]}