{"api_version":"1","generated_at":"2026-05-30T17:23:10+00:00","cve":"CVE-2026-23247","urls":{"html":"https://cve.report/CVE-2026-23247","api":"https://cve.report/api/cve/CVE-2026-23247.json","docs":"https://cve.report/api","cve_org":"https://www.cve.org/CVERecord?id=CVE-2026-23247","nvd":"https://nvd.nist.gov/vuln/detail/CVE-2026-23247"},"summary":{"title":"tcp: secure_seq: add back ports to TS offset","description":"In the Linux kernel, the following vulnerability has been resolved:\n\ntcp: secure_seq: add back ports to TS offset\n\nThis reverts 28ee1b746f49 (\"secure_seq: downgrade to per-host timestamp offsets\")\n\ntcp_tw_recycle went away in 2017.\n\nZhouyan Deng reported off-path TCP source port leakage via\nSYN cookie side-channel that can be fixed in multiple ways.\n\nOne of them is to bring back TCP ports in TS offset randomization.\n\nAs a bonus, we perform a single siphash() computation\nto provide both an ISN and a TS 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secure_seq: add back ports to TS offset","CVE":"CVE-2026-23247","Year":"2026"},"notes":[{"CveYear":"2026","CveId":"23247","Ordinal":"1","NoteData":"In the Linux kernel, the following vulnerability has been resolved:\n\ntcp: secure_seq: add back ports to TS offset\n\nThis reverts 28ee1b746f49 (\"secure_seq: downgrade to per-host timestamp offsets\")\n\ntcp_tw_recycle went away in 2017.\n\nZhouyan Deng reported off-path TCP source port leakage via\nSYN cookie side-channel that can be fixed in multiple ways.\n\nOne of them is to bring back TCP ports in TS offset randomization.\n\nAs a bonus, we perform a single siphash() computation\nto provide both an ISN and a TS offset.","Type":"Description","Title":"tcp: secure_seq: add back ports to TS offset"}]}}}