CVE-2025-37952 ksmbd: Fix UAF in __close_file_table_ids
A use-after-free in the Linux kernel's ksmbd module allows attackers to potentially execute code or escalate privileges via race conditions.
- Exploited in the wild
- Not known
- Login needed
- Any signed-in user
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2025-37952?
CVE-2025-37952 is a high-severity use after free vulnerability in Linux kernel, published on 20 May 2025. Any signed-in user can exploit it over the network, with no action from the victim.
Official description
In the Linux kernel, the following vulnerability has been resolved:
ksmbd: Fix UAF in __close_file_table_ids
A use-after-free is possible if one thread destroys the file via __ksmbd_close_fd while another thread holds a reference to it. The existing checks on fp->refcount are not sufficient to prevent this.
The fix takes ft->lock around the section which removes the file from the file table. This prevents two threads acquiring the same file pointer via __close_file_table_ids, as well as the other functions which retrieve a file from the IDR and which already use this same lock.
Weakness: CWE-416
Which versions are affected by CVE-2025-37952?
It affects 1 product.
Products include Linux kernel.
How do I fix CVE-2025-37952?
Apply the vendor's patch.
Upgrade to the fixed version. These bugs are found with fuzzing and sanitisers and avoided by memory-safe languages. More about Use after free.
Is CVE-2025-37952 being exploited?
There is no known exploitation of CVE-2025-37952 in the wild and no public exploit code.
Other vulnerabilities in Linux kernel
Sources
Also known as BELL-CVE-2025-37952, DEBIAN-CVE-2025-37952, GHSA-5m2x-9h8v-h39x, ROOT-OS-DEBIAN-12-CVE-2025-37952, ROOT-OS-UBUNTU-2204-CVE-2025-37952, ROOT-OS-UBUNTU-2404-CVE-2025-37952 and 1 more.