{"id":"ALPINE-CVE-2023-4091","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":"2026-09-15T08:17:48.394997871Z","published":"2023-11-03T08:15:08.197Z","upstream":["CVE-2023-4091"],"references":[{"type":"ADVISORY","url":"https://security.alpinelinux.org/vuln/CVE-2023-4091"}],"affected":[{"package":{"name":"samba","ecosystem":"Alpine:v3.18","purl":"pkg:apk/alpine/samba?arch=source"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"4.18.0"},{"fixed":"4.18.8-r0"}]}],"ecosystem_specific":{},"database_specific":{"source":"https://storage.googleapis.com/cve-osv-conversion/alpine/ALPINE-CVE-2023-4091.json"}},{"package":{"name":"samba","ecosystem":"Alpine:v3.19","purl":"pkg:apk/alpine/samba?arch=source"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"4.18.0"},{"fixed":"4.18.8-r0"}]}],"ecosystem_specific":{},"database_specific":{"source":"https://storage.googleapis.com/cve-osv-conversion/alpine/ALPINE-CVE-2023-4091.json"}},{"package":{"name":"samba","ecosystem":"Alpine:v3.20","purl":"pkg:apk/alpine/samba?arch=source"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"4.18.0"},{"fixed":"4.18.8-r0"}]}],"ecosystem_specific":{},"database_specific":{"source":"https://storage.googleapis.com/cve-osv-conversion/alpine/ALPINE-CVE-2023-4091.json"}},{"package":{"name":"samba","ecosystem":"Alpine:v3.21","purl":"pkg:apk/alpine/samba?arch=source"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"4.18.0"},{"fixed":"4.18.8-r0"}]}],"ecosystem_specific":{},"database_specific":{"source":"https://storage.googleapis.com/cve-osv-conversion/alpine/ALPINE-CVE-2023-4091.json"}},{"package":{"name":"samba","ecosystem":"Alpine:v3.22","purl":"pkg:apk/alpine/samba?arch=source"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"4.18.0"},{"fixed":"4.18.8-r0"}]}],"ecosystem_specific":{},"database_specific":{"source":"https://storage.googleapis.com/cve-osv-conversion/alpine/ALPINE-CVE-2023-4091.json"}},{"package":{"name":"samba","ecosystem":"Alpine:v3.23","purl":"pkg:apk/alpine/samba?arch=source"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"4.18.0"},{"fixed":"4.18.8-r0"}]}],"ecosystem_specific":{},"database_specific":{"source":"https://storage.googleapis.com/cve-osv-conversion/alpine/ALPINE-CVE-2023-4091.json"}},{"package":{"name":"samba","ecosystem":"Alpine:v3.24","purl":"pkg:apk/alpine/samba?arch=source"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"4.18.0"},{"fixed":"4.18.8-r0"}]}],"ecosystem_specific":{},"database_specific":{"source":"https://storage.googleapis.com/cve-osv-conversion/alpine/ALPINE-CVE-2023-4091.json"}}],"schema_version":"1.9.0","severity":[{"type":"CVSS_V3","score":"CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:H/A:N"}]}