What is CVE-2025-40099?

CVE-2025-40099 is a critical-severity vulnerability in Linux. CVSS score: 9.4/10. Published 2025-10-30.

How severe is CVE-2025-40099?

Critical severity. CVSS v3 base score is 9.4 out of 10.

Vulnerability in Linux

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.

EPSS: 0.002 (8.7th percentile) — read the EPSS interpretation.

CVSS v3 metric

CVSS v3 base score 9.4 (Critical). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:L/A:H.

Affected products

Linux — versions 4ecce920e13ace16a5ba45efe8909946c28fb2ad, 4.11, 0

References

416baaa9-dc9f-4396-8d5f-8c081fb06d67
416baaa9-dc9f-4396-8d5f-8c081fb06d67
416baaa9-dc9f-4396-8d5f-8c081fb06d67
416baaa9-dc9f-4396-8d5f-8c081fb06d67
416baaa9-dc9f-4396-8d5f-8c081fb06d67

Frequently asked questions

What is CVE-2025-40099?: CVE-2025-40099 is a critical-severity vulnerability in Linux. CVSS score: 9.4/10. Published 2025-10-30.
How severe is CVE-2025-40099?: Critical severity. CVSS v3 base score is 9.4 out of 10.