CVE-2026-46072 ntfs3: add buffer boundary checks to run_unpack()
A crafted NTFS image triggers an out-of-bounds heap read in the Linux kernel ntfs3 driver, potentially causing crashes or leaking memory.
- Exploited in the wild
- Not known
- Login needed
- Any signed-in user
- Attackable
- Local or same network only
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2026-46072?
CVE-2026-46072 is a medium-severity memory corruption vulnerability in Linux kernel, published on 27 May 2026. It can only be exploited from the same machine or local network, with no action from the victim.
Official description
In the Linux kernel, the following vulnerability has been resolved:
ntfs3: add buffer boundary checks to run_unpack()
run_unpack() checks `run_buf < run_last` at the top of the while loop but then reads size_size and offset_size bytes via run_unpack_s64() without verifying they fit within the remaining buffer. A crafted NTFS image with truncated run data in an MFT attribute triggers an OOB heap read of up to 15 bytes when the filesystem is mounted.
Add boundary checks before each run_unpack_s64() call to ensure the declared field size does not exceed the remaining buffer.
Found by fuzzing with a source-patched harness (LibAFL + QEMU).
Which versions are affected by CVE-2026-46072?
It affects 1 product.
Products include Linux kernel.
How do I fix CVE-2026-46072?
Apply the vendor's patch.
Upgrade to the fixed version. Memory-safe languages, compiler hardening and fuzzing prevent most new cases. More about Memory corruption.
Is CVE-2026-46072 being exploited?
There is no known exploitation of CVE-2026-46072 in the wild and no public exploit code.
Other vulnerabilities in Linux kernel
Sources
Also known as AZL-88497, BELL-CVE-2026-46072, DEBIAN-CVE-2026-46072, GHSA-h65x-x69q-35px, ROOT-OS-DEBIAN-12-CVE-2026-46072, ROOT-OS-UBUNTU-2204-CVE-2026-46072 and 2 more.