CVE-2023-53360 NFSv4.2: Rework scratch handling for READ_PLUS (again)
A double-free vulnerability in the Linux kernel's NFSv4.2 READ_PLUS handling can cause a system crash when decoding hole segments.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2023-53360?
CVE-2023-53360 is a critical use after free vulnerability in Linux kernel, published on 17 Sep 2025. An attacker can exploit it over the internet without logging in, with no action from the victim.
Official description
In the Linux kernel, the following vulnerability has been resolved:
NFSv4.2: Rework scratch handling for READ_PLUS (again)
I found that the read code might send multiple requests using the same nfs_pgio_header, but nfs4_proc_read_setup() is only called once. This is how we ended up occasionally double-freeing the scratch buffer, but also means we set a NULL pointer but non-zero length to the xdr scratch buffer. This results in an oops the first time decoding needs to copy something to scratch, which frequently happens when decoding READ_PLUS hole segments.
I fix this by moving scratch handling into the pageio read code. I provide a function to allocate scratch space for decoding read replies, and free the scratch buffer when the nfs_pgio_header is freed.
Weakness: CWE-415
Which versions are affected by CVE-2023-53360?
It affects 1 product.
Products include Linux kernel.
How do I fix CVE-2023-53360?
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-2023-53360 being exploited?
There is no known exploitation of CVE-2023-53360 in the wild and no public exploit code.
Other vulnerabilities in Linux kernel
Sources
Also known as BELL-CVE-2023-53360, DEBIAN-CVE-2023-53360, GHSA-4v4w-685q-cqmx, UBUNTU-CVE-2023-53360.