{"schema":"threatline.record/2","record":{"id":"CVE-2026-100659","aliases":["GHSA-q9pg-8h3j-8hvm"],"summary":"Netty 4.2.0 through 4.2.17 HTTP/3 Request Routing Bypass","details":"Netty's HTTP/3 codec (io.netty:netty-codec-http3) in versions 4.2.0.Final through 4.2.17.Final does not enforce the RFC 9114 requirement that the :authority pseudo-header field and a literal host header field, when both present, carry the same value. A remote unauthenticated peer can send a single HEADERS frame containing both fields with differing, attacker-controlled values; the request is accepted and delivered to the application with two conflicting authorities, allowing routing, virtual-host, and access-control decisions to be bypassed when different components in the request path consult different fields. This issue is fixed in 4.2.18.Final.","categories":["Frameworks"],"product":"netty","vendor":"netty","ecosystem":null,"affected_ranges":[{"source":"CVE List","source_url":"https://www.cve.org/CVERecord?id=CVE-2026-100659","source_modified_at":"2026-09-28T18:17:29.170Z","fetched_at":"2026-10-23T18:52:38.922436Z","product":"netty","vendor":"netty","versions":[{"version":"4.2.0.Final","status":"affected","versionType":"custom","lessThan":"4.2.18.Final"},{"version":"4.2.18.Final","status":"unaffected","versionType":"custom"}],"defaultStatus":"unaffected"}],"fixed_versions":[{"source":"CVE List","source_url":"https://www.cve.org/CVERecord?id=CVE-2026-100659","source_modified_at":"2026-09-28T18:17:29.170Z","fetched_at":"2026-10-23T18:52:38.922436Z","package":{"name":"netty","ecosystem":null},"version":"4.2.18.Final","basis":"first unaffected version stated in the CVE record"}],"cvss":6.9,"severity":"Medium","kev":{"listed":false},"epss":{"probability":0.00236,"percentile":0.1373,"score_date":"2026-10-23"},"published_at":"2026-09-26T13:23:26.859Z","modified_at":"2026-09-28T18:17:29.170Z","provenance":[{"source":"CVE List","url":"https://www.cve.org/CVERecord?id=CVE-2026-100659","fetched_at":"2026-10-23T18:52:38.922436Z","source_modified_at":"2026-09-28T18:17:29.170Z"},{"source":"EPSS","url":"https://api.first.org/data/v1/epss?cve=CVE-2026-100659","fetched_at":"2026-10-23T18:42:43.628194Z","source_modified_at":"2026-10-23"}],"sources":["CVE List","EPSS"],"references":[{"source":"CVE List","url":"https://github.com/netty/netty/security/advisories/GHSA-q9pg-8h3j-8hvm","tags":["vendor-advisory"]},{"source":"CVE List","url":"https://www.vulncheck.com/advisories/netty-4.2.0-through-4.2.18-http-3-request-routing-bypass","tags":["third-party-advisory"]}],"locations":[],"motoko_assessment":{"status":"requires_architecture_review","automatic_remediation":false},"cve_state":"PUBLISHED","cvss_source":"CVE List","ssvc":{"exploitation":"none","automatable":"yes","technical_impact":"partial","assessed_at":"2026-09-28T18:16:52.799456Z"},"classification":{"method":"product-first software-layer rules","rules_version":"2.1","matched_on":"product","confidence":"heuristic","reviewed":false},"change_timestamp":"2026-09-28T18:17:29.170Z","content_hash":"3f86de3d74edc7720f31c11c3f90621f6325c89a5908db42faa7ea6885124d54"}}