{"id":"CVE-2026-73507","title":"Netty is an asynchronous, event-driven network application framework","summary":"Netty is an asynchronous, event-driven network application framework. Prior to 4.1.136.Final and 4.2.16.Final, io.netty.handler.codec.xml.XmlFrameDecoder.decode() failed to preserve closing-tag parser state across invocations, so an unau…","severity":"high","cvss":7.5,"cvssVector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H","cwe":["CWE-400","CWE-835"],"vendor":"netty","product":"netty","affected":["netty < 4.1.136","netty >= 4.2.0, < 4.2.16"],"patched":["netty 4.2.16"],"published":"2026-08-13","updated":"2026-09-23","sourceUpdated":"2026-09-23T15:40:24.057","source":"NVD","sourceUrl":"https://nvd.nist.gov/vuln/detail/CVE-2026-73507","references":[{"url":"https://github.com/netty/netty/commit/5b68c61f37aa4a3045cba624cbea239655c9003b","label":"security-advisories@github.com"},{"url":"https://github.com/netty/netty/commit/bb2ff68a1fb71cb4b0eb9a9e17b66c52aff680c6","label":"security-advisories@github.com"},{"url":"https://github.com/netty/netty/releases/tag/netty-4.1.136.Final","label":"security-advisories@github.com"},{"url":"https://github.com/netty/netty/releases/tag/netty-4.2.16.Final","label":"security-advisories@github.com"},{"url":"https://github.com/netty/netty/security/advisories/GHSA-v74w-7mr3-4qg3","label":"security-advisories@github.com"},{"url":"https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-73507.json"},{"url":"https://access.redhat.com/security/cve/CVE-2026-73507"},{"url":"https://bugzilla.redhat.com/show_bug.cgi?id=2515374"},{"url":"https://www.cve.org/CVERecord?id=CVE-2026-73507"},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2026-73507"},{"url":"https://access.redhat.com/errata/RHSA-2026:71675"}],"tags":["nvd","csaf","vex","red-hat"],"epss":0.00793,"epssPercentile":0.56152,"ingestedAt":"2026-09-09T21:22:45.533Z","slug":"CVE-2026-73507","body":"## Overview\n\nNetty is an asynchronous, event-driven network application framework. Prior to 4.1.136.Final and 4.2.16.Final, io.netty.handler.codec.xml.XmlFrameDecoder.decode() failed to preserve closing-tag parser state across invocations, so an unauthenticated remote attacker could trickle-feed repeated </ sequences that repeatedly rescanned the accumulated buffer and exhausted an EventLoop thread's CPU, causing denial of service with a maxFrameLength of 1 MB. This issue is fixed in versions 4.1.136.Final and 4.2.16.Final.\n\n## Affected\n\n- `netty < 4.1.136`\n- `netty >= 4.2.0, < 4.2.16`\n\n## Remediation\n\nUpgrade past the affected range:\n\n- `netty 4.2.16`\n\n## Vendor advisories\n\n- **RHSA-2026:71675** · Red Hat · fixed in: Red Hat build of Apache Camel 4.18.4 for Spring Boot 3.5.16 · released 2026-09-24 · [advisory](https://access.redhat.com/errata/RHSA-2026:71675)\n- **Red Hat VEX** · Important · affected: Red Hat Single Sign-On 7 · no fix planned: Red Hat Single Sign-On 7 · updated 2026-10-16 · [vex](https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-73507.json)","depth":"twilight","depthScore":41,"depthScoreParts":{"impact":41.3,"likelihood":0.2,"exploitation":0,"ransomware":0},"changes":[]}