Vulnerability in Linux

CVE-2026-64392

In the Linux kernel, the following vulnerability has been resolved: ksmbd: use opener credentials for delete-on-close Delete-on-close can be completed by deferred or durable handle teardown, where no request work is available. Both the base-file unlink and the ADS xattr removal consequently run with the ksmbd worker credentials and can bypass filesystem permission checks. Run both operations with the credentials captured in struct file when the handle was opened. This preserves the authenticated user's fsuid, fsgid, supplementary groups and capability restrictions at final close.

EPSS: 0.005 (38.9th percentile) — read the EPSS interpretation.

CVSS v3 metric

CVSS v3 base score 9.1 (Critical). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:H.

Affected products

References

Frequently asked questions

What is CVE-2026-64392?
CVE-2026-64392 is a critical-severity vulnerability in Linux. CVSS score: 9.1/10. Published 2026-07-25.
How severe is CVE-2026-64392?
Critical severity. CVSS v3 base score is 9.1 out of 10.