Bug 2455339 (CVE-2026-31410)

Summary: CVE-2026-31410 kernel: ksmbd: use volume UUID in FS_OBJECT_ID_INFORMATION
Product: [Other] Security Response Reporter: OSIDB Bzimport <bzimport>
Component: vulnerabilityAssignee: Product Security DevOps Team <prodsec-dev>
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OS: Linux   
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A flaw was found in ksmbd in the Linux kernel. This vulnerability occurs because ksmbd incorrectly uses a fallback identifier when a volume's Universal Unique Identifier (UUID) is not available in FS_OBJECT_ID_INFORMATION. This could lead to improper volume identification.
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Description OSIDB Bzimport 2026-04-06 09:01:45 UTC 
In the Linux kernel, the following vulnerability has been resolved:

ksmbd: use volume UUID in FS_OBJECT_ID_INFORMATION

Use sb->s_uuid for a proper volume identifier as the primary choice.
For filesystems that do not provide a UUID, fall back to stfs.f_fsid
obtained from vfs_statfs().
Comment 1 Keith Grant 2026-04-06 11:53:34 UTC 
Upstream advisory:
https://lore.kernel.org/linux-cve-announce/2026040629-CVE-2026-31410-5b44@gregkh/T