{"id":"CVE-2026-47244","url":"https://www.cyber-defence.io/tools/cve/CVE-2026-47244","generatedAt":"2026-10-28T01:14:03.110Z","title":"Netty is a network application framework for development of protocol servers and clients.","description":"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, DefaultHttp2Connection.DefaultEndpoint initialises maxActiveStreams/maxStreams to Integer.MAX_VALUE, and Http2Settings never inserts SETTINGS_MAX_CONCURRENT_STREAMS by default (Http2Settings.java:305-307 only clamps a user-supplied value). Unless the application explicitly calls initialSettings().maxConcurrentStreams(n), a Netty HTTP/2 server advertises no limit and enforces none locally. Each open stream allocates a DefaultStream object, PropertyMap slots, flow-controller state and IntObjectHashMap entry; with ~2^30 permissible odd stream IDs a single TCP connection can create hundreds of thousands of long-lived stream objects. This is also the precondition for CVE-2023-44487-style Rapid-Reset amplification, where the absence of a low concurrent cap multiplies backend work. Versions 4.1.135.Final and 4.2.15.Final patch the issue.","published":"2026-06-12T15:16:29.000Z","lastModified":"2026-06-17T10:54:26.000Z","status":"Analyzed","sourceIdentifier":"security-advisories@github.com","cvss":{"version":"3.1","score":5.3,"severity":"MEDIUM","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L"},"cwe":["CWE-400"],"affected":["netty/netty"],"epss":{"score":0.00384,"percentile":0.32203,"date":"2026-10-26","history":[]},"kev":{"listed":false},"exploits":{"count":0,"verified":false,"firstPublished":null,"source":"Exploit-DB (https://gitlab.com/exploit-database/exploitdb)","entries":[]},"verdict":{"level":"low","text":"Lower severity and a low EPSS score (0.38%). Track it; it rarely justifies an emergency change on its own."},"changes":[],"references":[{"url":"https://github.com/netty/netty/releases/tag/netty-4.1.135.Final","tags":["Release Notes"],"source":"security-advisories@github.com"},{"url":"https://github.com/netty/netty/releases/tag/netty-4.2.15.Final","tags":["Release Notes"],"source":"security-advisories@github.com"},{"url":"https://github.com/netty/netty/security/advisories/GHSA-5x3r-wrvg-rp6q","tags":["Vendor Advisory"],"source":"security-advisories@github.com"}],"sources":{"nvd":"https://nvd.nist.gov/vuln/detail/CVE-2026-47244","epss":"https://www.first.org/epss/","kev":"https://www.cisa.gov/known-exploited-vulnerabilities-catalog","exploitdb":"https://www.exploit-db.com/"},"licence":"CC BY 4.0 — link back to the CVE Explorer if you publish the results; upstream data remains subject to its own terms."}