{"id":"CVE-2026-90153","summary":"ksmbd: bound smb_check_perm_dacl() ACE walks by DACL size","details":"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-\u003esize 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-\u003esize, 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","modified":"2026-11-01T02:31:08.125957438Z","published":"2026-09-17T16:06:46.296Z","related":["openSUSE-SU-2026:11880-1"],"database_specific":{"cna_assigner":"Linux","osv_generated_from":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/90xxx/CVE-2026-90153.json"},"references":[{"type":"WEB","url":"https://git.kernel.org/stable/c/79decd88dd3f0d42e7fb0689b1a7853bfa302459"},{"type":"WEB","url":"https://git.kernel.org/stable/c/8e4f75e979c1d9a51b0a48ac33d0cfd5f039ec67"},{"type":"WEB","url":"https://git.kernel.org/stable/c/930dcdd888eabf166589e020dcbf6d15b5e13305"},{"type":"WEB","url":"https://git.kernel.org/stable/c/a2051ffe452afad52f580b85a3fd8851933b1e7c"},{"type":"WEB","url":"https://git.kernel.org/stable/c/a29f57a14c939586d84d7fd6a029bd1fd170098f"},{"type":"WEB","url":"https://git.kernel.org/stable/c/a4a307d149327dad5fb25187e1b03cebd1b04de6"},{"type":"ADVISORY","url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/90xxx/CVE-2026-90153.json"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-90153"},{"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":"8f0541186e9ad1b62accc9519cc2b7a7240272a7"},{"fixed":"930dcdd888eabf166589e020dcbf6d15b5e13305"},{"fixed":"a2051ffe452afad52f580b85a3fd8851933b1e7c"},{"fixed":"a29f57a14c939586d84d7fd6a029bd1fd170098f"},{"fixed":"a4a307d149327dad5fb25187e1b03cebd1b04de6"},{"fixed":"8e4f75e979c1d9a51b0a48ac33d0cfd5f039ec67"},{"fixed":"79decd88dd3f0d42e7fb0689b1a7853bfa302459"}]},{"type":"GIT","repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","events":[{"introduced":"5.15.62"},{"fixed":"5.16"}]},{"type":"GIT","repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","events":[{"introduced":"5.18.18"},{"fixed":"5.19"}]},{"type":"GIT","repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","events":[{"introduced":"5.19.2"},{"fixed":"5.20"}]},{"type":"GIT","repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","events":[{"introduced":"cb69d4d6f709f87c94afa28ae64c501576692171"}]},{"type":"GIT","repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","events":[{"introduced":"6e8f4abf584253cbaa596ea4ad13110cf61cd4c9"}]},{"type":"GIT","repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","events":[{"introduced":"8e33102309bd6839b2e2e158f93a7b378cb4655d"}]}],"versions":["v5.15.224","v5.15.223","v5.15.222","v5.15.221","v5.15.220","v5.15.219","v5.15.218","v5.15.217","v5.15.216","v5.15.215","v5.15.214","v5.15.213","v5.15.212","v5.15.211","v5.15.210","v5.15.209","v5.15.208","v5.15.207","v5.15.206","v5.15.205","v5.15.204","v5.15.203","v5.15.202","v5.15.201","v5.15.200","v5.15.199","v5.15.198","v5.15.197","v5.15.196","v5.15.195","v5.15.194","v5.15.193","v5.15.192","v5.15.191","v5.15.190","v5.15.189","v5.15.188","v5.15.187","v5.15.186","v5.15.185","v5.15.184","v5.15.183","v5.15.182","v5.15.181","v5.15.180","v5.15.179","v5.15.178","v5.15.177","v5.15.176","v5.15.175","v5.15.174","v5.15.173","v5.15.172","v5.15.171","v5.15.170","v5.15.169","v5.15.168","v5.15.167","v5.15.166","v5.15.165","v5.15.164","v5.15.163","v5.15.162","v5.15.161","v5.15.160","v5.15.159","v5.15.158","v5.15.157","v5.15.156","v5.15.155","v5.15.154","v5.15.153","v5.15.152","v5.15.151","v5.15.150","v5.15.149","v5.15.148","v5.15.147","v5.15.146","v5.15.145","v5.15.144","v5.15.143","v5.15.142","v5.15.141","v5.15.140","v5.15.139","v5.15.138","v5.15.137","v5.15.136","v5.15.135","v5.15.134","v5.15.133","v5.15.132","v5.15.131","v5.15.130","v5.15.129","v5.15.128","v5.15.127","v5.15.126","v5.15.125","v5.15.124","v5.15.123","v5.15.122","v5.15.121","v5.15.120","v5.15.119","v5.15.118","v5.15.117","v5.15.116","v5.15.115","v5.15.114","v5.15.113","v5.15.112","v5.15.111","v5.15.110","v5.15.109","v5.15.108","v5.15.107","v5.15.106","v5.15.105","v5.15.104","v5.15.103","v5.15.102","v5.15.101","v5.15.100","v5.15.99","v5.15.98","v5.15.97","v5.15.96","v5.15.95","v5.15.94","v5.15.93","v5.15.92","v5.15.91","v5.15.90","v5.15.89","v5.15.88","v5.15.87","v5.15.86","v5.15.85","v5.15.84","v5.15.83","v5.15.82","v5.15.81","v5.15.80","v5.15.79","v5.15.78","v5.15.77","v5.15.76","v5.15.75","v5.15.74","v5.15.73","v5.15.72","v5.15.71","v5.15.70","v5.15.69","v5.15.68","v5.15.67","v5.15.66","v5.15.65","v5.15.64","v5.15.63","v5.15.62","v5.18.19","v5.18.18","v5.19.17","v5.19.16","v5.19.15","v5.19.14","v5.19.13","v5.19.12","v5.19.11","v5.19.10","v5.19.9","v5.19.8","v5.19.7","v5.19.6","v5.19.5","v5.19.4","v5.19.3","v5.19.2"],"database_specific":{"source":"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-90153.json"}},{"package":{"name":"Kernel","ecosystem":"Linux"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"6.0.0"},{"fixed":"6.1.191"}]},{"type":"ECOSYSTEM","events":[{"introduced":"6.2.0"},{"fixed":"6.6.157"}]}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