{"id":"CVE-2026-56862","revision":"51077cecff694c2c8fed39628f930e6b","records":[{"revision":"51077cecff694c2c8fed39628f930e6b","observedAt":"2026-10-23T15:48:27.903+00:00","statement":{"source":"cve-program","id":"CVE-2026-56862","aliases":[],"title":"Limit handshake messages we are willing to accept post-handshake in crypto/tls","description":"Handshake messages, such as KeyUpdate, are always considered as state-advancing, regardless of whether a handshake has been completed or not. As a result, a malicious client can keep sending KeyUpdate messages to force the server to keep performing key derivation operations indefinitely.","state":0,"publishedAt":"2026-08-13T21:58:53.216+00:00","modifiedAt":"2026-08-14T15:29:41.741+00:00","affected":[{"ecosystem":"https://pkg.go.dev","name":"crypto/tls","ranges":[],"versions":[],"rawVersionEvidence":"{\n                    \"vendor\": \"Go standard library\",\n                    \"product\": \"crypto/tls\",\n                    \"collectionURL\": \"https://pkg.go.dev\",\n                    \"packageName\": \"crypto/tls\",\n                    \"versions\": [\n                        {\n                            \"version\": \"0\",\n                            \"lessThan\": \"1.25.13\",\n                            \"status\": \"affected\",\n                            \"versionType\": \"semver\"\n                        },\n                        {\n                            \"version\": \"1.26.0-0\",\n                            \"lessThan\": \"1.26.6\",\n                            \"status\": \"affected\",\n                            \"versionType\": \"semver\"\n                        },\n                        {\n                            \"version\": \"1.27.0-0\",\n                            \"lessThan\": \"1.27.0-rc.3\",\n                            \"status\": \"affected\",\n                            \"versionType\": \"semver\"\n                        }\n                    ],\n                    \"programRoutines\": [\n                        {\n                            \"name\": \"Conn.readRecordOrCCS\"\n                        },\n                        {\n                            \"name\": \"Conn.Handshake\"\n                        },\n                        {\n                            \"name\": \"Conn.HandshakeContext\"\n                        },\n                        {\n                            \"name\": \"Conn.Read\"\n                        },\n                        {\n                            \"name\": \"Conn.Write\"\n                        },\n                        {\n                            \"name\": \"Dial\"\n                        },\n                        {\n                            \"name\": \"DialWithDialer\"\n                        },\n                        {\n                            \"name\": \"Dialer.Dial\"\n                        },\n                        {\n                            \"name\": \"Dialer.DialContext\"\n                        },\n                        {\n                            \"name\": \"QUICConn.HandleData\"\n                        },\n                        {\n                            \"name\": \"QUICConn.Start\"\n                        }\n                    ],\n                    \"defaultStatus\": \"unaffected\"\n                }"}],"metrics":[],"references":["https://go.dev/issue/80528","https://go.dev/cl/804261","https://groups.google.com/g/golang-announce/c/94pEornpRlI","https://pkg.go.dev/vuln/GO-2026-6090"],"sourceUrl":"https://www.cve.org/CVERecord?id=CVE-2026-56862","license":"CVE Program Terms of Use","key":"cve-program:CVE-2026-56862","identifiers":["CVE-2026-56862"]},"retained":false,"historicalAffected":[]}],"coverage":[]}