CVE-2026-63967 iio: imu: st_lsm6dsx: fix stack leak in tagged FIFO buffer
A local attacker can read uninitialized kernel stack memory via the ST LSM6DSX IMU driver's tagged FIFO interface, potentially exposing sensitive data.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Local or same network only
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2026-63967?
CVE-2026-63967 is a vulnerability in Linux, published on 19 Jul 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:
iio: imu: st_lsm6dsx: fix stack leak in tagged FIFO buffer
The tagged FIFO path declares iio_buff on the stack with __aligned(8) but no initializer, but there is a hole in the structure, which will then leak to userspace as ST_LSM6DSX_SAMPLE_SIZE bytes (6) will be copied, but the space between that and the timestamp are not initialized.
Commit c14edb4d0bdc ("iio:imu:st_lsm6dsx Fix alignment and data leak issues") moved the untagged FIFO path to a kzalloc'd buffer in hw->scan, but for the tagged path it only added the alignment qualifier and not the initializer :(
Fix this by just zero-initializing the structure on the stack.
Which versions are affected by CVE-2026-63967?
How do I fix CVE-2026-63967?
Apply the vendor's patch.
Is CVE-2026-63967 being exploited?
There is no known exploitation of CVE-2026-63967 in the wild and no public exploit code.
Sources
Also known as BELL-CVE-2026-63967, DEBIAN-CVE-2026-63967, GHSA-vghm-prgp-x82v, ROOT-OS-UBUNTU-2204-CVE-2026-63967, UBUNTU-CVE-2026-63967.