{"cve":"CVE-2026-64380","nvd":{"published":"2026-07-25T10:17:21.220","modified":"2026-10-19T21:17:34.383","status":"Modified","description":"In the Linux kernel, the following vulnerability has been resolved:\n\nsmb: client: harden POSIX SID length parsing\n\nposix_info_sid_size() reads sid[1] to obtain the subauthority count,\nbut its existing boundary check still accepts buffers with only one\nremaining byte. Require two bytes before reading sid[1] so all client\npaths that reuse the helper reject truncated POSIX SIDs safely.","cvss_v4":null,"cvss_v3":{"version":"3.1","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:H","score":8.2},"cwes":["CWE-125"],"references":["https://git.kernel.org/stable/c/0de5b8e76847f5de26f364a82c6602c4881c30da","https://git.kernel.org/stable/c/171605aed68380c2fa75dff9b3a1ed427c50065b","https://git.kernel.org/stable/c/4213c1208978483021d7d125c131de3985d38f61","https://git.kernel.org/stable/c/427eb7eb46425fec845a43e861f3d6e2899cae59","https://git.kernel.org/stable/c/46a84715a015cb48e1b9c219dc88c03d8a541ea4"],"products":["linux:linux_kernel"],"source":"nvd","synced_at":"2026-10-21T03:43:09.190223697+00:00"},"epss":{"cve":"CVE-2026-64380","score":0.00443,"percentile":0.38254,"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."]}