{"id":"CVE-2026-23247","summary":"tcp: secure_seq: add back ports to TS offset","details":"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.","modified":"2026-05-23T03:57:03.272367679Z","published":"2026-03-18T10:05:09.353Z","database_specific":{"cna_assigner":"Linux","osv_generated_from":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/23xxx/CVE-2026-23247.json"},"references":[{"type":"WEB","url":"https://git.kernel.org/stable/c/165573e41f2f66ef98940cf65f838b2cb575d9d1"},{"type":"WEB","url":"https://git.kernel.org/stable/c/46e5b0d7cf55821527adea471ffe52a5afbd9caf"},{"type":"WEB","url":"https://git.kernel.org/stable/c/eae2f14ab2efccdb7480fae7d42c4b0116ef8805"},{"type":"ADVISORY","url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/23xxx/CVE-2026-23247.json"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-23247"},{"type":"PACKAGE","url":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git"}],"affected":[{"ranges":[{"type":"GIT","repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","events":[{"introduced":"28ee1b746f493b7c62347d714f58fbf4f70df4f0"},{"fixed":"eae2f14ab2efccdb7480fae7d42c4b0116ef8805"},{"fixed":"46e5b0d7cf55821527adea471ffe52a5afbd9caf"},{"fixed":"165573e41f2f66ef98940cf65f838b2cb575d9d1"}]},{"type":"GIT","repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","events":[{"introduced":"0"},{"last_affected":"443fac9f2618b93cbc5ab068dc594530236b3a23"}]}],"versions":["v4.10.13","v4.10.12","v4.10.11","v4.10.10","v4.10.9","v4.10.8","v4.10.7","v4.10.6","v4.10","v4.10.5","v4.10.4","v4.10.3","v4.10.2","v4.10.1","v4.9","v4.10-rc8","v4.10-rc3","v4.10-rc1","v4.10-rc7","v4.10-rc6","v4.10-rc2","v4.10-rc5","v4.10-rc4","v4.9-rc7","v4.9-rc6","v4.9-rc8","v4.9-rc1","v4.9-rc5","v4.9-rc3","v4.9-rc4","v4.9-rc2","v4.8","v4.8-rc8","v4.8-rc2","v4.8-rc1","v4.8-rc7","v4.8-rc6","v4.8-rc5","v4.8-rc4","v4.8-rc3","v4.7","v4.7-rc4","v4.7-rc2","v4.7-rc1","v4.7-rc7","v4.7-rc6","v4.7-rc3","v4.7-rc5","v4.6","v4.6-rc1","v4.6-rc6","v4.6-rc4","v4.6-rc7","v4.6-rc5","v4.5-rc4","v4.6-rc2","v4.6-rc3","v4.5","v4.4","v4.5-rc1","v4.5-rc6","v4.5-rc2","v4.5-rc7","v4.5-rc5","v4.5-rc3","v4.4-rc1","v4.4-rc2","v4.4-rc8","v4.4-rc3","v4.4-rc7","v4.4-rc5","v4.4-rc6","v4.4-rc4","v4.3","v4.3-rc1","v4.3-rc6","v4.3-rc4","v4.3-rc2","v4.3-rc7","v4.3-rc5","v4.3-rc3","v4.2","v4.2-rc2","v4.2-rc1","v4.2-rc8","v4.2-rc4","v4.2-rc6","v4.2-rc7","v4.0-rc5","v4.2-rc5","v4.2-rc3","v4.1-rc2","v4.1","v4.1-rc1","v4.1-rc8","v4.1-rc7","v4.1-rc6","v4.1-rc3","v4.1-rc4","v4.0","v4.1-rc5","v4.0-rc1","v4.0-rc2","v4.0-rc7","v4.0-rc3","v4.0-rc6","v4.0-rc4","v3.19","v3.19-rc7","v3.19-rc5","v3.19-rc1","v3.19-rc6","v3.19-rc4","v3.18-rc1","v3.19-rc3","v3.19-rc2","v3.18","v3.18-rc7","v3.18-rc6","v3.18-rc2","v3.18-rc3","v3.18-rc4","v3.18-rc5","v3.17","v3.17-rc1","v3.17-rc7","v3.17-rc2","v3.17-rc4","v3.16","v3.17-rc5","v3.17-rc6","v3.17-rc3","v3.16-rc7","v3.16-rc1","v3.16-rc3","v3.16-rc5","v3.16-rc6","v3.16-rc2","v3.16-rc4","v3.13","v3.15","v3.15-rc5","v3.15-rc8","v3.15-rc1","v3.15-rc6","v3.15-rc3","v3.15-rc7","v3.15-rc2","v3.15-rc4","v3.14","v3.14-rc4","v3.14-rc8","v3.14-rc7","v3.14-rc6","v3.14-rc1","v3.14-rc2","v3.14-rc5","v3.14-rc3","v3.13-rc6","v3.13-rc8","v3.12","v3.13-rc7","v3.13-rc1","v3.13-rc4","v3.13-rc3","v3.13-rc5","v3.13-rc2","v3.12-rc7","v3.12-rc3","v3.12-rc6","v3.12-rc1","v3.12-rc5","v3.11","v3.12-rc2","v3.12-rc4","v3.11-rc7","v3.11-rc2","v3.11-rc5","v3.11-rc1","v3.11-rc3","v3.11-rc4","v3.11-rc6","v3.10-rc2","v3.10","v3.10-rc7","v3.10-rc6","v3.10-rc1","v3.10-rc5","v3.10-rc3","v3.10-rc4","v3.9","v3.9-rc2","v3.9-rc7","v3.9-rc8","v3.9-rc3","v3.9-rc6","v3.9-rc5","v3.9-rc4","v3.9-rc1","v3.8","v3.8-rc7","v3.8-rc6","v3.8-rc5","v3.8-rc2","v3.8-rc1","v3.8-rc3","v3.8-rc4","v3.7","v3.7-rc1","v3.6","v3.7-rc6","v3.7-rc7","v3.7-rc3","v3.7-rc8","v3.7-rc2","v3.7-rc4","v3.7-rc5","v3.6-rc7","v3.6-rc1","v3.5-rc3","v3.6-rc6","v3.6-rc5","v3.5","v3.6-rc3","v3.6-rc4","v3.6-rc2","v3.4-rc4","v3.5-rc7","v3.5-rc5","v3.5-rc6","v3.5-rc2","v3.5-rc1","v3.5-rc4","v3.4","v3.4-rc2","v3.4-rc1","v3.4-rc7","v3.4-rc6","v3.4-rc3","v3.4-rc5","v3.3","v3.3-rc6","v3.3-rc3","v3.3-rc7","v3.3-rc2","v3.3-rc5","v3.2","v3.3-rc4","v3.3-rc1","v3.2-rc4","v3.2-rc7","v3.2-rc6","v3.2-rc5","v3.2-rc3","v3.1","v3.2-rc2","v3.2-rc1","v3.1-rc1","v3.1-rc9","v3.1-rc8","v3.1-rc10","v3.1-rc7","v3.1-rc3","v3.1-rc2","v3.1-rc4","v3.1-rc5","v3.0","v3.1-rc6","v3.0-rc7","v3.0-rc4","v3.0-rc6","v3.0-rc5","v3.0-rc3","v3.0-rc1","v2.6.39","v3.0-rc2","v2.6.38","v2.6.39-rc2","v2.6.39-rc7","v2.6.39-rc5","v2.6.39-rc1","v2.6.38-rc7","v2.6.39-rc6","v2.6.39-rc4","v2.6.39-rc3","v2.6.37","v2.6.38-rc1","v2.6.38-rc8","v2.6.38-rc2","v2.6.38-rc6","v2.6.38-rc5","v2.6.38-rc4","v2.6.38-rc3","v2.6.37-rc4","v2.6.37-rc2","v2.6.36","v2.6.37-rc5","v2.6.37-rc8","v2.6.37-rc7","v2.6.37-rc6","v2.6.37-rc1","v2.6.37-rc3","v2.6.36-rc6","v2.6.35-rc4","v2.6.36-rc8","v2.6.35","v2.6.36-rc7","v2.6.36-rc3","v2.6.36-rc5","v2.6.36-rc4","v2.6.36-rc2","v2.6.36-rc1","v2.6.35-rc5","v2.6.35-rc6","v2.6.34","v2.6.35-rc3","v2.6.35-rc1","v2.6.35-rc2","v2.6.34-rc7","v2.6.34-rc6","v2.6.34-rc5","v2.6.34-rc4","v2.6.34-rc3","v2.6.34-rc2","v2.6.34-rc1","v2.6.33","v2.6.33-rc6","v2.6.33-rc8","v2.6.33-rc4","v2.6.33-rc5","v2.6.33-rc3","v2.6.33-rc7","v2.6.33-rc2","v2.6.32","v2.6.33-rc1","v2.6.32-rc8","v2.6.32-rc7","v2.6.32-rc6","v2.6.31","v2.6.32-rc5","v2.6.32-rc4","v2.6.32-rc2","v2.6.32-rc1","v2.6.32-rc3","v2.6.31-rc9","v2.6.31-rc1","v2.6.31-rc7","v2.6.31-rc8","v2.6.31-rc6","v2.6.30-rc6","v2.6.30","v2.6.31-rc4","v2.6.31-rc5","v2.6.31-rc3","v2.6.31-rc2","v2.6.30-rc7","v2.6.30-rc8","v2.6.30-rc5","v2.6.30-rc3","v2.6.30-rc4","v2.6.30-rc1","v2.6.30-rc2","v2.6.29","v2.6.29-rc8","v2.6.29-rc7","v2.6.29-rc5","v2.6.29-rc1","v2.6.29-rc6","v2.6.29-rc4","v2.6.29-rc3","v2.6.29-rc2","v2.6.28","v2.6.28-rc7","v2.6.28-rc9","v2.6.28-rc8","v2.6.28-rc6","v2.6.28-rc5","v2.6.28-rc4","v2.6.28-rc2","v2.6.28-rc3","v2.6.28-rc1","v2.6.27","v2.6.27-rc7","v2.6.27-rc9","v2.6.27-rc8","v2.6.27-rc5","v2.6.27-rc6","v2.6.27-rc4","v2.6.27-rc1","v2.6.27-rc3","v2.6.27-rc2","v2.6.26","v2.6.26-rc9","v2.6.26-rc8","v2.6.26-rc3","v2.6.26-rc7","v2.6.26-rc6","v2.6.26-rc5","v2.6.26-rc4","v2.6.26-rc2","v2.6.26-rc1","v2.6.25","v2.6.25-rc7","v2.6.25-rc9","v2.6.25-rc8","v2.6.25-rc6","v2.6.25-rc5","v2.6.25-rc3","v2.6.25-rc4","v2.6.24","v2.6.25-rc2","v2.6.25-rc1","v2.6.24-rc8","v2.6.24-rc7","v2.6.24-rc6","v2.6.24-rc5","v2.6.24-rc4","v2.6.24-rc3","v2.6.24-rc2","v2.6.24-rc1","v2.6.23","v2.6.23-rc9","v2.6.23-rc8","v2.6.23-rc5","v2.6.23-rc7","v2.6.23-rc6","v2.6.23-rc4","v2.6.23-rc3","v2.6.23-rc2","v2.6.23-rc1","v2.6.22","v2.6.22-rc7","v2.6.22-rc6","v2.6.22-rc5","v2.6.22-rc4","v2.6.22-rc3","v2.6.22-rc2","v2.6.22-rc1","v2.6.21","v2.6.21-rc7","v2.6.21-rc6","v2.6.21-rc5","v2.6.21-rc4","v2.6.21-rc3","v2.6.21-rc2","v2.6.21-rc1","v2.6.20-rc7","v2.6.20-rc6","v2.6.20-rc5","v2.6.20-rc4","v2.6.20-rc3","v2.6.20-rc1","v2.6.20-rc2","v2.6.19-rc2","v2.6.18","v2.6.19-rc1","v2.6.18-rc6","v2.6.18-rc5","v2.6.18-rc3","v2.6.18-rc2","v2.6.18-rc1","v2.6.17","v2.6.17-rc4","v2.6.17-rc6","v2.6.17-rc5","v2.6.17-rc3","v2.6.17-rc2","v2.6.17-rc1","v2.6.16","v2.6.16-rc6","v2.6.16-rc4","v2.6.16-rc5","v2.6.16-rc3","v2.6.16-rc2","v2.6.16-rc1","v2.6.15-rc7","v2.6.15-rc5","v2.6.15-rc4","v2.6.15-rc2","v2.6.15-rc1","v2.6.14-rc3","v2.6.14-rc2","v2.6.14-rc1","v2.6.13","v2.6.13-rc7","v2.6.13-rc6","v2.6.13-rc5","v2.6.13-rc3","v2.6.13-rc4","v2.6.13-rc2","v2.6.13-rc1","v2.6.12-rc4","v2.6.12-rc3","v2.6.12-rc2"],"database_specific":{"source":"https://storage.googleapis.com/osv-test-cve-osv-conversion/osv-output/CVE-2026-23247.json"}},{"package":{"name":"Kernel","ecosystem":"Linux"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"4.11.0"},{"fixed":"6.18.17"}]},{"type":"ECOSYSTEM","events":[{"introduced":"6.19.0"},{"fixed":"6.19.7"}]}],"database_specific":{"source":"https://storage.googleapis.com/osv-test-cve-osv-conversion/osv-output/CVE-2026-23247.json"}}],"schema_version":"1.7.5"}