{"schemaVersion":3,"id":"CVE-2026-93569","aliases":["UBUNTU-CVE-2026-93569","DEBIAN-CVE-2026-93569"],"status":"published","duplicateOf":null,"title":null,"description":"A flaw was found in Netty. A remote unauthenticated attacker can exploit a vulnerability in Netty's HTTP/1 to HTTP/2 conversion process. When an HTTP/1 request includes both an absolute-form request-target and a conflicting Host header, Netty incorrectly prioritizes the Host header for the HTTP/2 :authority field, discarding the original request-target authority. This inconsistency can allow an attacker to bypass security controls in Netty-based proxies or gateways, potentially leading to unauthorized access, cache poisoning, or misrouting of requests.","dates":{"published":"2026-09-18T14:27:54.015Z","modified":"2026-10-19T10:37:38.533Z","reserved":null,"kevAdded":[],"kevDue":[]},"cvss":{"headline":{"score":8.2,"severity":"high","version":"3.1","versionLabel":"v3.1","source":"CVE.org","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:H/A:N","computed":false,"selection":"backend-summary"},"metrics":[{"version":"3.1","versionLabel":"v3.1","source":"CVE.org","score":8.2,"severity":"high","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:H/A:N","exploitability":null,"impact":null,"computed":false},{"version":"3.1","versionLabel":"v3.1","source":"OSV · Ubuntu","score":8.2,"severity":"high","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:H/A:N","exploitability":10,"impact":7,"computed":true},{"version":"3.1","versionLabel":"v3.1","source":"OSV · 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