{"cve":"CVE-2026-90153","nvd":{"published":"2026-09-17T17:17:08.370","modified":"2026-10-19T09:19:05.287","status":"Received","description":"In the Linux kernel, the following vulnerability has been resolved:\n\nksmbd: bound smb_check_perm_dacl() ACE walks by DACL size\n\nsmb_check_perm_dacl() validates that the DACL fits inside the NT\nsecurity descriptor, but then bounds its two ACE walks by the\nremaining NTSD length (acl_size) rather than the DACL's declared\nsize (pdacl_size).\n\nWhen pdacl->size is smaller than the trailing NTSD buffer, bytes\nafter the declared DACL boundary - still inside the stored security\ndescriptor - are parsed as ACEs during access checks.  A crafted\nDACL can place an access-granting ACE beyond pdacl->size, and the\ncurrent code accepts it during SMB2_CREATE access validation, while\nparse_dacl() and smb_inherit_dacl() stop at pdacl_size.\n\nBound both ACE walks by pdacl_size to match the DACL boundary\nsemantics used elsewhere in the server.\n\nValidation:\n- semantic KUnit harness shows the post-boundary ACE is selected\n  before the fix and rejected (EACCES) after it\n- linux master (7.2-rc6), x86_64","cvss_v4":null,"cvss_v3":{"version":"3.1","vector":"CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:N","score":8.1},"cwes":[],"references":["https://git.kernel.org/stable/c/79decd88dd3f0d42e7fb0689b1a7853bfa302459","https://git.kernel.org/stable/c/8e4f75e979c1d9a51b0a48ac33d0cfd5f039ec67","https://git.kernel.org/stable/c/a2051ffe452afad52f580b85a3fd8851933b1e7c","https://git.kernel.org/stable/c/a29f57a14c939586d84d7fd6a029bd1fd170098f","https://git.kernel.org/stable/c/a4a307d149327dad5fb25187e1b03cebd1b04de6"],"products":[],"source":"nvd","synced_at":"2026-10-19T22:55:23.253742848+00:00"},"epss":{"cve":"CVE-2026-90153","score":0.00478,"percentile":0.40958,"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."]}