{"id":"CVE-2023-4091","summary":"Samba: smb clients can truncate files with read-only permissions","details":"A vulnerability was discovered in Samba, where the flaw allows SMB clients to truncate files, even with read-only permissions when the Samba VFS module \"acl_xattr\" is configured with \"acl_xattr:ignore system acls = yes\". The SMB protocol allows opening files when the client requests read-only access but then implicitly truncates the opened file to 0 bytes if the client specifies a separate OVERWRITE create disposition request. The issue arises in configurations that bypass kernel file system permissions checks, relying solely on Samba's permissions.","modified":"2026-08-12T03:51:32.855458140Z","published":"2023-11-03T07:56:35.611Z","related":["ALSA-2023:6744","ALSA-2023:7467","SUSE-SU-2023:4040-1","SUSE-SU-2023:4046-1","SUSE-SU-2023:4059-1","SUSE-SU-2023:4096-1","USN-6425-3","openSUSE-SU-2024:13332-1"],"database_specific":{"cwe_ids":["CWE-276"],"osv_generated_from":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2023/4xxx/CVE-2023-4091.json","cna_assigner":"redhat"},"references":[{"type":"WEB","url":"https://access.redhat.com/downloads/content/package-browser/"},{"type":"WEB","url":"https://lists.debian.org/debian-lts-announce/2024/04/msg00015.html"},{"type":"WEB","url":"https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/ZUMVALLFFDFC53JZMUWA6HPD7HUGAP5I/"},{"type":"WEB","url":"https://www.samba.org/samba/security/CVE-2023-4091.html"},{"type":"ADVISORY","url":"https://access.redhat.com/errata/RHSA-2023:6209"},{"type":"ADVISORY","url":"https://access.redhat.com/errata/RHSA-2023:6744"},{"type":"ADVISORY","url":"https://access.redhat.com/errata/RHSA-2023:7371"},{"type":"ADVISORY","url":"https://access.redhat.com/errata/RHSA-2023:7408"},{"type":"ADVISORY","url":"https://access.redhat.com/errata/RHSA-2023:7464"},{"type":"ADVISORY","url":"https://access.redhat.com/errata/RHSA-2023:7467"},{"type":"ADVISORY","url":"https://access.redhat.com/security/cve/CVE-2023-4091"},{"type":"ADVISORY","url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2023/4xxx/CVE-2023-4091.json"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2023-4091"},{"type":"ADVISORY","url":"https://security.netapp.com/advisory/ntap-20231124-0002/"},{"type":"REPORT","url":"https://bugzilla.redhat.com/show_bug.cgi?id=2241882"},{"type":"REPORT","url":"https://bugzilla.samba.org/show_bug.cgi?id=15439"}],"affected":[{"ranges":[{"type":"GIT","repo":"https://github.com/samba-team/samba","events":[{"introduced":"0"},{"fixed":"7ec207cd4146919e4ee88e5522647c169baf6922"},{"introduced":"a597a8767fabfe85ee0bcf869407e770a0c3e184"},{"fixed":"f1c0d4f1feb8105d22307e29150e0b7d59b5fed9"},{"introduced":"b7921852ad6ac048abbbe577b9faced2d694c685"},{"fixed":"d9e90993b4049bac99227c8f3c8823df45f7f46d"}],"database_specific":{"extracted_events":[{"introduced":"0"},{"fixed":"4.17.12"},{"introduced":"4.18.0"},{"fixed":"4.18.8"},{"introduced":"4.19.0"},{"fixed":"4.19.1"}],"source":"CPE_RANGE","cpe":"cpe:2.3:a:samba:samba:*:*:*:*:*:*:*:*"}}],"versions":["samba-4.17.11","samba-4.18.7","samba-4.19.0","samba-4.18.6","samba-4.17.10","samba-4.17.9","samba-4.18.4","samba-4.18.3","samba-4.17.8","samba-4.18.2","samba-4.18.1","samba-4.17.7","ldb-2.7.2","ldb-2.6.2","samba-4.17.6","samba-4.18.0","samba-4.17.5","samba-4.17.4","samba-4.17.2","samba-4.17.1","samba-4.17.0","samba-4.17.0rc5","samba-4.17.0rc4","samba-4.17.0rc3","samba-4.17.0rc2","samba-4.17.0rc1","ldb-2.6.1","tevent-0.13.0","tdb-1.4.7","tevent-0.12.1","talloc-2.3.4","tevent-0.12.0","samba-4.16.0rc1","ldb-2.6.0","tdb-1.4.6","ldb-2.5.0","tdb-1.4.5","samba-4.15.0rc1","ldb-2.4.0","tdb-1.4.4","talloc-2.3.3","tevent-0.11.0","samba-4.14.0rc1","talloc-2.3.2","samba-4.13.0rc1","ldb-2.2.0","ldb-2.1.1","samba-4.12.0rc1","ldb-2.1.0","tevent-0.10.2","tdb-1.4.3","talloc-2.3.1","tevent-0.10.1","tdb-1.4.2","talloc-2.3.0","samba-4.11.0rc1","ldb-2.0.5","tdb-1.4.1","ldb-1.6.3","tevent-0.10.0","talloc-2.2.0","tdb-1.4.0","ldb-1.6.2","tevent-0.9.39","talloc-2.1.16","tdb-1.3.18","ldb-1.6.1","samba-4.10.0rc1","ldb-1.5.2","tevent-0.9.38","talloc-2.1.15","tdb-1.3.17","ldb-1.5.1","ldb-1.5.0","samba-4.9.0rc1","ldb-1.4.1","talloc-2.1.14","tdb-1.3.16","tevent-0.9.37","ldb-1.4.0","talloc-2.1.13","talloc-2.1.12","ldb-1.3.2","tevent-0.9.36","samba-4.8.0rc1","ldb-1.3.1","tevent-0.9.35","talloc-2.1.11","tevent-0.9.34","ldb-1.3.0","ldb-1.2.2","tdb-1.3.15","ldb-1.2.1","tevent-0.9.33","talloc-2.1.10","samba-4.7.0rc1","ldb-1.2.0","tdb-1.3.14","tevent-0.9.32","ldb-1.1.31","ldb-1.1.30","tdb-1.3.13","talloc-2.1.9","samba-4.6.0rc1","ldb-1.1.29","tdb-1.3.12","ldb-1.1.28","tevent-0.9.31","tdb-1.3.11","tevent-0.9.30","samba-4.5.0rc1","ldb-1.1.27","tevent-0.9.29","talloc-2.1.8","tdb-1.3.10","talloc-2.1.7","tdb-1.3.9","talloc-2.1.6","tevent-0.9.28","ldb-1.1.26","tevent-0.9.27","samba-4.4.0rc1","ldb-1.1.25","ldb-1.1.23","talloc-2.1.5","tdb-1.3.8","tevent-0.9.26","ldb-1.1.22","talloc-2.1.4","samba-4.3.0rc1","ldb-1.1.21","tdb-1.3.7","talloc-2.1.3","tdb-1.3.6","tevent-0.9.25","tdb-1.3.5","talloc-2.1.2","tevent-0.9.24","tevent-0.9.23","ldb-1.1.20","ldb-1.1.19","tdb-1.3.4","tdb-1.3.3","ldb-1.1.18","tdb-1.3.2","samba-4.2.0rc1","tevent-0.9.22","tdb-1.3.1","tdb-1.3.0","talloc-2.1.1","ldb-1.1.17","tdb-1.2.13","tevent-0.9.21","tevent-0.9.20","talloc-2.1.0","tevent-0.9.19","ldb-1.1.16","tdb-1.2.12","tevent-0.9.18","ldb-1.1.15","ldb-1.1.14","tdb-1.2.11","talloc-2.0.8","samba-4.0.0rc1","ldb-1.1.13","samba-4.0.0beta8","ldb-1.1.12","ldb-1.1.11","samba-4.0.0beta7","tevent-0.9.17","samba-4.0.0beta6","ldb-1.1.10","ldb-1.1.9","samba-4.0.0beta5","samba-4.0.0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