CVE-2025-40099

CVE-2025-40099 is a security vulnerability that is still awaiting full analysis and scoring. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low.

Key facts

Description

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.

Frequently asked questions

What is CVE-2025-40099?
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.
Is CVE-2025-40099 being actively exploited?
It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (8th percentile), an estimate of the probability of exploitation in the next 30 days.
How do I fix CVE-2025-40099?
Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
Does CVE-2025-40099 have an EU (EUVD) identifier?
Yes. CVE-2025-40099 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2025-36979.
When was CVE-2025-40099 published?
CVE-2025-40099 was published on 2025-10-30 and last updated on 2026-06-17.

References