{"cve":"CVE-2026-23247","nvd":{"published":"2026-03-18T11:16:16.723","modified":"2026-10-21T13:18:35.110","status":"Modified","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 offset.","cvss_v4":null,"cvss_v3":{"version":"3.1","vector":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H","score":5.5},"cwes":[],"references":["https://git.kernel.org/stable/c/165573e41f2f66ef98940cf65f838b2cb575d9d1","https://git.kernel.org/stable/c/46e5b0d7cf55821527adea471ffe52a5afbd9caf","https://git.kernel.org/stable/c/5da5662181ef8a251e3ba564903002c2e87de452","https://git.kernel.org/stable/c/e873e8c16b2fb743a381a9e59c108e63512301ec","https://git.kernel.org/stable/c/eae2f14ab2efccdb7480fae7d42c4b0116ef8805"],"products":["linux:linux_kernel"],"source":"nvd","synced_at":"2026-10-22T16:41:11.231219466+00:00"},"epss":{"cve":"CVE-2026-23247","score":0.00167,"percentile":0.05897,"date":"2026-10-25"},"kev":null,"osv":[],"attribution":["This product uses the NVD API but is not endorsed or certified by the NVD.","EPSS scores: FIRST Exploit Prediction Scoring System, https://www.first.org/epss","Known exploited vulnerabilities: CISA Known Exploited Vulnerabilities Catalog, https://www.cisa.gov/known-exploited-vulnerabilities-catalog","Package advisories: OSV (https://osv.dev), from the GitHub Advisory Database, PyPA, Go, RustSec and other ecosystem databases, under CC-BY 4.0 or CC0","CVE records: the CVE Program's CVE List (https://www.cve.org), under its terms of use (https://www.cve.org/Legal/TermsOfUse). CVE is a registered trademark of The MITRE Corporation; this product is not affiliated with the CVE Program."]}