{"affected":[{"defaultStatus":"unaffected","ecosystem":"https://gitlab.com/samba-team/samba","packageName":"samba","product":"Samba","source":"CNA: redhat","vendor":"Samba","versions":[{"lessThan":"4.25.1","status":"affected","version":"4.25.0","versionType":"semver"}]},{"defaultStatus":"unaffected","ecosystem":"https://access.redhat.com/downloads/content/package-browser/","packageName":"samba","product":"Red Hat Enterprise Linux 10","source":"CNA: redhat","vendor":"Red Hat","versions":[]},{"defaultStatus":"unaffected","ecosystem":"https://access.redhat.com/downloads/content/package-browser/","packageName":"samba","product":"Red Hat Enterprise Linux 6","source":"CNA: redhat","vendor":"Red Hat","versions":[]},{"defaultStatus":"unaffected","ecosystem":"https://access.redhat.com/downloads/content/package-browser/","packageName":"samba4","product":"Red Hat Enterprise Linux 6","source":"CNA: redhat","vendor":"Red Hat","versions":[]},{"defaultStatus":"unaffected","ecosystem":"https://access.redhat.com/downloads/content/package-browser/","packageName":"samba","product":"Red Hat Enterprise Linux 7","source":"CNA: redhat","vendor":"Red Hat","versions":[]},{"defaultStatus":"unaffected","ecosystem":"https://access.redhat.com/downloads/content/package-browser/","packageName":"samba","product":"Red Hat Enterprise Linux 8","source":"CNA: redhat","vendor":"Red Hat","versions":[]},{"defaultStatus":"unaffected","ecosystem":"https://access.redhat.com/downloads/content/package-browser/","packageName":"samba","product":"Red Hat Enterprise Linux 9","source":"CNA: redhat","vendor":"Red Hat","versions":[]},{"defaultStatus":"unaffected","ecosystem":"https://access.redhat.com/downloads/content/package-browser/","packageName":"openshift/ose-rhel-coreos-8","product":"Red Hat OpenShift Container Platform 4","source":"CNA: redhat","vendor":"Red Hat","versions":[]},{"defaultStatus":"unaffected","ecosystem":"https://access.redhat.com/downloads/content/package-browser/","packageName":"openshift/ose-rhel-coreos-9","product":"Red Hat OpenShift Container Platform 4","source":"CNA: redhat","vendor":"Red Hat","versions":[]},{"defaultStatus":"unaffected","ecosystem":"https://access.redhat.com/downloads/content/package-browser/","packageName":"openshift/ose-rhel-coreos-9","product":"Red Hat OpenShift Container Platform 5","source":"CNA: redhat","vendor":"Red Hat","versions":[]}],"cveId":"CVE-2026-109411","cwes":["CWE-178"],"description":"An access control bypass flaw was identified in Samba's vfs_ceph_rgw module in it's openat() function. An authenticated user can bypass access controls to read or overwrite restricted files on shares configured with the experimental vfs_ceph_rgw module. When a client requests an existing file using mismatched character casing, the module fails to perform a case-insensitive lookup correctly, causing the server to treat the operation as creating a new file. As a result, the server skips standard permission checks on the existing file, allowing the attacker to access or overwrite sensitive data owned by other users.","epss":{"date":"2026-11-04","percentile":0.51252,"score":0.00649},"exploits":[],"kev":null,"metrics":[{"score":8.1,"severity":"high","source":"CNA: redhat","vector":"CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:N","version":"3.1"},{"score":8.1,"severity":"high","source":"NVD: secalert@redhat.com","vector":"CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:N","version":"3.1"}],"modifiedAt":1793830666553,"publishedAt":1793215065459,"references":[{"source":"CNA: redhat","tags":["vdb-entry","x_refsource_REDHAT"],"url":"https://access.redhat.com/security/cve/CVE-2026-109411"},{"source":"CNA: redhat","tags":[],"url":"https://attachments.samba.org/attachment.cgi?id=19294"},{"source":"CNA: redhat","tags":[],"url":"https://attachments.samba.org/attachment.cgi?id=19295"},{"source":"CNA: redhat","tags":["issue-tracking","x_refsource_REDHAT"],"url":"https://bugzilla.redhat.com/show_bug.cgi?id=2552136"},{"source":"CNA: redhat","tags":[],"url":"https://bugzilla.samba.org/show_bug.cgi?id=16276"},{"source":"secalert@redhat.com","tags":[],"url":"https://access.redhat.com/security/cve/CVE-2026-109411"},{"source":"secalert@redhat.com","tags":[],"url":"https://attachments.samba.org/attachment.cgi?id=19294"},{"source":"secalert@redhat.com","tags":[],"url":"https://attachments.samba.org/attachment.cgi?id=19295"},{"source":"secalert@redhat.com","tags":[],"url":"https://bugzilla.redhat.com/show_bug.cgi?id=2552136"},{"source":"secalert@redhat.com","tags":[],"url":"https://bugzilla.samba.org/show_bug.cgi?id=16276"}],"remediation":[{"kind":"workaround","source":"CNA: redhat","text":"Only shares configured with the vfs_ceph_rgw module are affected.\n\nTo mitigate this vulnerability, disable the experimental `vfs_ceph_rgw` module on any configured Samba shares. Edit `/etc/samba/smb.conf` to remove `ceph_rgw` from the `vfs objects` setting under the relevant share sections, then reload the Samba service:\n\n```\nsystemctl reload smb\n```\n\nWarning: Reloading or restarting the `smb` service may briefly interrupt active client sessions. Additionally, removing this module disables Ceph RGW integration for the affected shares.\n\nSetting ```case sensitive = yes``` on affected shares avoids the vulnerability, because the differently-cased name is then treated as a distinct object rather than resolving to the existing file. \n\nNote: This changes share behavior for clients that rely on case-insensitive name handling."}],"revision":"9aea1cec9dc3c649d6537c6b4881cd27ec30d67629eadf39074b4b3849484f79","sources":[{"modifiedAt":1793828916103,"name":"CNA: redhat","retrievedAt":1793830302317,"url":"https://www.cve.org/CVERecord?id=CVE-2026-109411"},{"modifiedAt":1793830666553,"name":"NVD","retrievedAt":1793838182355,"url":"https://nvd.nist.gov/vuln/detail/CVE-2026-109411"},{"modifiedAt":null,"name":"FIRST EPSS","retrievedAt":1793830322842,"url":"https://api.first.org/data/v1/epss?cve=CVE-2026-109411"}],"ssvc":{"assessedAt":1793288216528,"automatable":"no","exploitation":"none","source":"ADP: CISA-ADP","technicalImpact":"total"},"status":"published","title":"Samba: access control bypass via vfs_ceph_rgw case-insensitive open","updatedAt":1793838182355}