{"id":"CVE-2026-74696","revision":"898465a38c4741e9ac6139324951aae5","records":[{"revision":"898465a38c4741e9ac6139324951aae5","observedAt":"2026-10-23T15:48:27.903+00:00","statement":{"source":"cve-program","id":"CVE-2026-74696","aliases":[],"title":"tcp: fix TFO max_qlen accounting across reuseport migration","description":"In the Linux kernel, the following vulnerability has been resolved:\n\ntcp: fix TFO max_qlen accounting across reuseport migration\n\nA listener's TCP_FASTOPEN max_qlen stops being accurate and lets through\nfar more pending Fast Open requests than it was configured for.\n\nThis only shows up with SO_REUSEPORT listener migration, where closing a\nlistener hands its still-pending TFO children over to a surviving one.\n\nfastopenq.qlen is charged in tcp_fastopen_create_child() when the child\nis created and uncharged in reqsk_fastopen_remove() when the handshake\ncompletes.  The uncharge follows rsk_listener of the request the child\npoints at, and inet_reqsk_clone() has repointed the child at a new\nrequest owned by the new listener, so the ++ and the -- land on two\ndifferent sockets.  The new listener's qlen drifts negative and its\nlimit no longer binds.\n\nCharge the new listener during migration, like reqsk_queue_migrated()\nalready does for queue->young and queue->qlen.","state":0,"publishedAt":"2026-08-22T15:32:58.414+00:00","modifiedAt":"2026-10-16T19:16:09.811+00:00","affected":[{"ecosystem":"Vendor product","name":"Linux","ranges":[],"versions":[],"rawVersionEvidence":"{\n                    \"product\": \"Linux\",\n                    \"vendor\": \"Linux\",\n                    \"defaultStatus\": \"unaffected\",\n                    \"repo\": \"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git\",\n                    \"programFiles\": [\n                        \"net/ipv4/inet_connection_sock.c\"\n                    ],\n                    \"versions\": [\n                        {\n                            \"version\": \"54b92e84193749c9968aff2dd46e3b0f42643e18\",\n                            \"lessThan\": \"e98f0d80b9cccb5f828425d2004f9686e7d1ae24\",\n                            \"status\": \"affected\",\n                            \"versionType\": \"git\"\n                        },\n                        {\n                            \"version\": \"54b92e84193749c9968aff2dd46e3b0f42643e18\",\n                            \"lessThan\": \"b6247e0f96bd825ffb2005257f6177b5e642dee6\",\n                            \"status\": \"affected\",\n                            \"versionType\": \"git\"\n                        },\n                        {\n                            \"version\": \"54b92e84193749c9968aff2dd46e3b0f42643e18\",\n                            \"lessThan\": \"585fc5247d14939a561056aa2addd9b7c2b1f670\",\n                            \"status\": \"affected\",\n                            \"versionType\": \"git\"\n                        },\n                        {\n                            \"version\": \"54b92e84193749c9968aff2dd46e3b0f42643e18\",\n                            \"lessThan\": \"6e10ee56524a26b250229ad348637825646ddb88\",\n                            \"status\": \"affected\",\n                            \"versionType\": \"git\"\n                        },\n                        {\n                            \"version\": \"54b92e84193749c9968aff2dd46e3b0f42643e18\",\n                            \"lessThan\": \"a66e869cf0c90c1e47ae75f72b6482acbfc808ff\",\n                            \"status\": \"affected\",\n                            \"versionType\": \"git\"\n                        },\n                        {\n                            \"version\": \"54b92e84193749c9968aff2dd46e3b0f42643e18\",\n                            \"lessThan\": \"d974618b2097453778389d385e3741629c40e0a3\",\n                            \"status\": \"affected\",\n                            \"versionType\": \"git\"\n                        },\n                        {\n                            \"version\": \"54b92e84193749c9968aff2dd46e3b0f42643e18\",\n                            \"lessThan\": \"a0ab2ba83e35159d81cec830a92e885ecf8139be\",\n                            \"status\": \"affected\",\n                            \"versionType\": \"git\"\n                        }\n                    ]\n                }"},{"ecosystem":"Vendor product","name":"Linux","ranges":[],"versions":[],"rawVersionEvidence":"{\n                    \"product\": \"Linux\",\n                    \"vendor\": \"Linux\",\n                    \"defaultStatus\": \"affected\",\n                    \"repo\": \"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git\",\n                    \"programFiles\": [\n                        \"net/ipv4/inet_connection_sock.c\"\n                    ],\n                    \"versions\": [\n                        {\n                            \"version\": \"5.14\",\n                            \"status\": \"affected\"\n                        },\n                        {\n                            \"version\": \"0\",\n                            \"lessThan\": \"5.14\",\n                            \"status\": \"unaffected\",\n                            \"versionType\": \"semver\"\n                        },\n                        {\n                            \"version\": \"5.15.216\",\n                            \"lessThanOrEqual\": \"5.15.*\",\n                            \"status\": \"unaffected\",\n                            \"versionType\": \"semver\"\n                        },\n                        {\n                            \"version\": \"6.1.183\",\n                            \"lessThanOrEqual\": \"6.1.*\",\n                            \"status\": \"unaffected\",\n                            \"versionType\": \"semver\"\n                        },\n                        {\n                            \"version\": \"6.6.152\",\n                            \"lessThanOrEqual\": \"6.6.*\",\n                            \"status\": \"unaffected\",\n                            \"versionType\": \"semver\"\n                        },\n                        {\n                            \"version\": \"6.12.104\",\n                            \"lessThanOrEqual\": \"6.12.*\",\n                            \"status\": \"unaffected\",\n                            \"versionType\": \"semver\"\n                        },\n                        {\n                            \"version\": \"6.18.45\",\n                            \"lessThanOrEqual\": \"6.18.*\",\n                            \"status\": \"unaffected\",\n                            \"versionType\": \"semver\"\n                        },\n                        {\n                            \"version\": \"7.1.9\",\n                            \"lessThanOrEqual\": \"7.1.*\",\n                            \"status\": \"unaffected\",\n                            \"versionType\": \"semver\"\n                        },\n                        {\n                            \"version\": \"7.2\",\n                            \"lessThanOrEqual\": \"*\",\n                            \"status\": \"unaffected\",\n                            \"versionType\": \"original_commit_for_fix\"\n                        }\n                    ]\n                }"}],"metrics":[{"system":"CVSS 3.1","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H","score":7.5,"severity":"HIGH"}],"references":["https://git.kernel.org/stable/c/e98f0d80b9cccb5f828425d2004f9686e7d1ae24","https://git.kernel.org/stable/c/b6247e0f96bd825ffb2005257f6177b5e642dee6","https://git.kernel.org/stable/c/585fc5247d14939a561056aa2addd9b7c2b1f670","https://git.kernel.org/stable/c/6e10ee56524a26b250229ad348637825646ddb88","https://git.kernel.org/stable/c/a66e869cf0c90c1e47ae75f72b6482acbfc808ff","https://git.kernel.org/stable/c/d974618b2097453778389d385e3741629c40e0a3","https://git.kernel.org/stable/c/a0ab2ba83e35159d81cec830a92e885ecf8139be"],"sourceUrl":"https://www.cve.org/CVERecord?id=CVE-2026-74696","license":"CVE Program Terms of Use","key":"cve-program:CVE-2026-74696","identifiers":["CVE-2026-74696"]},"retained":false,"historicalAffected":[]}],"coverage":[]}