{"id":"CVE-2026-100655","title":"Netty (io.netty:netty-codec-http) versions up to and including 4.1.137.Final and from 4.2.0.Final through 4.2.17.Final accept an unlimited number of concurrent remote-initiated SPDY streams: SpdySessionHandler defaults localConcurrentStr…","summary":"Netty (io.netty:netty-codec-http) versions up to and including 4.1.137.Final and from 4.2.0.Final through 4.2.17.Final accept an unlimited number of concurrent remote-initiated SPDY streams: SpdySessionHandler defaults localConcurrentStr…","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-770"],"vendor":"netty","product":"netty","affected":["netty < 4.1.138.Final","netty >= 4.2.0.Final < 4.2.18.Final"],"published":"2026-09-26","updated":"2026-09-26","sourceUpdated":"2026-09-26T14:16:48.243","source":"NVD","sourceUrl":"https://nvd.nist.gov/vuln/detail/CVE-2026-100655","references":[{"url":"https://github.com/netty/netty/security/advisories/GHSA-rmcw-9fcq-wjq7","label":"disclosure@vulncheck.com"},{"url":"https://www.vulncheck.com/advisories/netty-before-4.1.138-final-denial-of-service-via-spdysessionhandler","label":"disclosure@vulncheck.com"}],"tags":["nvd","cve.org"],"ingestedAt":"2026-09-26T13:33:20.917Z","slug":"CVE-2026-100655","body":"## Overview\n\nNetty (io.netty:netty-codec-http) versions up to and including 4.1.137.Final and from 4.2.0.Final through 4.2.17.Final accept an unlimited number of concurrent remote-initiated SPDY streams: SpdySessionHandler defaults localConcurrentStreams to Integer.MAX_VALUE and exposes no API to change it. A remote peer that opens a SPDY connection and sends millions of SYN_STREAM frames with FLAG_FIN=0 causes the server to allocate unbounded heap and direct memory, eventually triggering a JVM OutOfMemoryError and crashing the service. Fixed in 4.1.138.Final and 4.2.18.Final.\n\n## Remediation\n\nRefer to the linked advisories for vendor-supplied fixes and affected version ranges.","depth":"twilight","depthScore":41,"depthScoreParts":{"impact":41.3,"likelihood":0,"exploitation":0,"ransomware":0},"changes":[]}