Vulnerability Description
In the Linux kernel, the following vulnerability has been resolved: ksmbd: serialize QUERY_DIRECTORY requests per file smb2_query_dir() stores a pointer to its stack-allocated private data in the ksmbd_file readdir_data. Concurrent QUERY_DIRECTORY requests using the same file handle can overwrite this pointer while an iterate_dir() callback is still using it, resulting in a stack use-after-free. Add a per-file mutex and hold it while accessing the shared directory enumeration state. The lock covers scan restart, dot entry state, readdir_data setup and iteration, and response construction. This prevents another request from replacing readdir_data.private before the current request has finished using it and also serializes the shared file position.
CVSS Score
CRITICAL
References
- https://git.kernel.org/stable/c/1426fd79102539bc0ab5c8fced047ad4313b9908
- https://git.kernel.org/stable/c/2a64dbf9c739ddf7a25a066507597bf89f8f73d2
- https://git.kernel.org/stable/c/64dac2d486ec1eb18dc00968b16a230b6b75ec24
- https://git.kernel.org/stable/c/a1d5d31cad593ea5e1b637f2f39c9ef6d09d1199
- https://git.kernel.org/stable/c/be6d26bf27499977c746abc163659915082348d8
- https://git.kernel.org/stable/c/fd22b039a5a05bc1d6818e9dcd1001fb432a829d
FAQ
What is CVE-2026-64397?
CVE-2026-64397 is a vulnerability with a CVSS score of 9.8 (CRITICAL). In the Linux kernel, the following vulnerability has been resolved: ksmbd: serialize QUERY_DIRECTORY requests per file smb2_query_dir() stores a pointer to its stack-allocated private data in the ks...
How severe is CVE-2026-64397?
CVE-2026-64397 has been rated CRITICAL with a CVSS base score of 9.8/10. This is considered a critical vulnerability requiring immediate attention.
Is there a patch for CVE-2026-64397?
Check the references section above for vendor advisories and patch information. Review vendor security bulletins for remediation guidance.