{"id":"UBUNTU-CVE-2026-42581","details":"Netty is an asynchronous, event-driven network application framework. Prior to 4.2.13.Final and 4.1.133.Final, HttpObjectDecoder strips a conflicting Content-Length header when a request carries both Transfer-Encoding: chunked and Content-Length, but only for HTTP/1.1 messages. The guard is absent for HTTP/1.0. An attacker that sends an HTTP/1.0 request with both headers causes Netty to decode the body as chunked while leaving Content-Length intact in the forwarded HttpMessage. Any downstream proxy or handler that trusts Content-Length over Transfer-Encoding will disagree on message boundaries, enabling request smuggling. This vulnerability is fixed in 4.2.13.Final and 4.1.133.Final.","modified":"2026-06-30T18:17:46.150884251Z","published":"2026-05-13T19:17:00Z","related":["USN-8401-1"],"upstream":["CVE-2026-42581"],"references":[{"type":"REPORT","url":"https://ubuntu.com/security/CVE-2026-42581"},{"type":"REPORT","url":"https://www.cve.org/CVERecord?id=CVE-2026-42581"},{"type":"REPORT","url":"https://github.com/netty/netty/security/advisories/GHSA-xxqh-mfjm-7mv9"},{"type":"ADVISORY","url":"https://ubuntu.com/security/notices/USN-8401-1"}],"affected":[{"package":{"name":"netty","ecosystem":"Ubuntu:Pro:14.04:LTS","purl":"pkg:deb/ubuntu/netty?arch=source&distro=esm-infra-legacy%2Ftrusty"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"1:3.2.6.Final-2+deb8u2ubuntu0.1~esm1"}]}],"versions":["1:3.2.6.Final-2","1:3.2.6.Final-2+deb8u2build0.14.04.1~esm1"],"ecosystem_specific":{"availability":"Available with Ubuntu Pro with Legacy support add-on: 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https://ubuntu.com/pro"},"database_specific":{"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2026/UBUNTU-CVE-2026-42581.json"}},{"package":{"name":"netty","ecosystem":"Ubuntu:Pro:20.04:LTS","purl":"pkg:deb/ubuntu/netty?arch=source&distro=esm-apps%2Ffocal"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"1:4.1.45-1ubuntu0.1~esm6"}]}],"versions":["1:4.1.33-1","1:4.1.33-2","1:4.1.33-3","1:4.1.45-1","1:4.1.45-1ubuntu0.1~esm1","1:4.1.45-1ubuntu0.1~esm2","1:4.1.45-1ubuntu0.1~esm3","1:4.1.45-1ubuntu0.1~esm4"],"ecosystem_specific":{"availability":"Available with Ubuntu Pro: https://ubuntu.com/pro","binaries":[{"binary_name":"libnetty-java","binary_version":"1:4.1.45-1ubuntu0.1~esm6"}]},"database_specific":{"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2026/UBUNTU-CVE-2026-42581.json"}},{"package":{"name":"netty","ecosystem":"Ubuntu:Pro:22.04:LTS","purl":"pkg:deb/ubuntu/netty?arch=source&distro=esm-apps%2Fjammy"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"1:4.1.48-4+deb11u2ubuntu0.1+esm3"}]}],"versions":["1:4.1.48-4","1:4.1.48-4+deb11u1build0.22.04.1","1:4.1.48-4+deb11u2build0.22.04.1","1:4.1.48-4+deb11u2ubuntu0.1~esm1","1:4.1.48-4+deb11u2ubuntu0.1~esm2","1:4.1.48-4+deb11u2ubuntu0.1","1:4.1.48-4+deb11u2ubuntu0.1+esm1"],"ecosystem_specific":{"binaries":[{"binary_version":"1:4.1.48-4+deb11u2ubuntu0.1+esm3","binary_name":"libnetty-java"}],"availability":"Available with Ubuntu Pro: https://ubuntu.com/pro"},"database_specific":{"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2026/UBUNTU-CVE-2026-42581.json"}},{"package":{"name":"netty","ecosystem":"Ubuntu:Pro:24.04:LTS","purl":"pkg:deb/ubuntu/netty?arch=source&distro=esm-apps%2Fnoble"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"1:4.1.48-9ubuntu0.1+esm3"}]}],"versions":["1:4.1.48-7","1:4.1.48-8","1:4.1.48-9","1:4.1.48-9ubuntu0.1~esm1","1:4.1.48-9ubuntu0.1~esm2","1:4.1.48-9ubuntu0.1","1:4.1.48-9ubuntu0.1+esm1"],"ecosystem_specific":{"availability":"Available with Ubuntu Pro: 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