CVE-2026-64392
CriticalCVSS 9.1Exploitation Probability (EPSS)
Low risk38th percentile - higher than 38% of all known CVEs
Summary
In the Linux kernel, the ksmbd filesystem runs the delete-on-close operation with the ksmbd worker credentials instead of the credentials of the user who opened the handle. This can bypass filesystem permission checks.
Risk Assessment
An attacker can delete files they do not have permission to, leading to data loss or integrity compromise.
Recommendation
Apply the Linux kernel patch that runs delete-on-close operations with the credentials captured when the handle was opened.
Original NVD description (English source)
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.