Bug 2407341 (CVE-2025-40099)

Summary: CVE-2025-40099 kernel: cifs: parse_dfs_referrals: prevent oob on malformed input
Product: [Other] Security Response Reporter: OSIDB Bzimport <bzimport>
Component: vulnerabilityAssignee: Product Security DevOps Team <prodsec-dev>
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Version: unspecifiedKeywords: Security
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OS: Linux   
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Description OSIDB Bzimport 2025-10-30 10:02:36 UTC 
In the Linux kernel, the following vulnerability has been resolved:

cifs: parse_dfs_referrals: prevent oob on malformed input

Malicious SMB server can send invalid reply to FSCTL_DFS_GET_REFERRALS

- reply smaller than sizeof(struct get_dfs_referral_rsp)
- reply with number of referrals smaller than NumberOfReferrals in the
header

Processing of such replies will cause oob.

Return -EINVAL error on such replies to prevent oob-s.
Comment 1 Jon Moroney 2025-10-30 16:29:14 UTC 
Upstream advisory:
https://lore.kernel.org/linux-cve-announce/2025103017-CVE-2025-40099-fdf0@gregkh/T