{"api_version":"1","generated_at":"2026-07-29T19:30:00+00:00","cve":"CVE-2026-64380","urls":{"html":"https://cve.report/CVE-2026-64380","api":"https://cve.report/api/cve/CVE-2026-64380.json","docs":"https://cve.report/api","cve_org":"https://www.cve.org/CVERecord?id=CVE-2026-64380","nvd":"https://nvd.nist.gov/vuln/detail/CVE-2026-64380"},"summary":{"title":"smb: client: harden POSIX SID length parsing","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. 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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. 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Require two bytes before reading sid[1] so all client\npaths that reuse the helper reject truncated POSIX SIDs safely.","Type":"Description","Title":"smb: client: harden POSIX SID length parsing"}]}}}