CVE-2022-50394 i2c: ismt: Fix an out-of-bounds bug in ismt_access()
A local attacker can trigger an out-of-bounds read in the i2c ismt driver, potentially causing a system crash or arbitrary code execution.
- 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-2022-50394?
CVE-2022-50394 is a high-severity memory corruption vulnerability in Linux kernel, published on 18 Sep 2025. 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:
i2c: ismt: Fix an out-of-bounds bug in ismt_access()
When the driver does not check the data from the user, the variable 'data->block[0]' may be very large to cause an out-of-bounds bug.
The following log can reveal it:
[ 33.995542] i2c i2c-1: ioctl, cmd=0x720, arg=0x7ffcb3dc3a20 [ 33.995978] ismt_smbus 0000:00:05.0: I2C_SMBUS_BLOCK_DATA: WRITE [ 33.996475] ================================================================== [ 33.996995] BUG: KASAN: out-of-bounds in ismt_access.cold+0x374/0x214b [ 33.997473] Read of size 18446744073709551615 at addr ffff88810efcfdb1 by task ismt_poc/485 [ 33.999450] Call Trace: [ 34.001849] memcpy+0x20/0x60 [ 34.002077] ismt_access.cold+0x374/0x214b [ 34.003382] __i2c_smbus_xfer+0x44f/0xfb0 [ 34.004007] i2c_smbus_xfer+0x10a/0x390 [ 34.004291] i2cdev_ioctl_smbus+0x2c8/0x710 [ 34.005196] i2cdev_ioctl+0x5ec/0x74c
Fix this bug by checking the size of 'data->block[0]' first.
Weakness: CWE-125
Which versions are affected by CVE-2022-50394?
It affects 1 product.
Products include Linux kernel.
How do I fix CVE-2022-50394?
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-2022-50394 being exploited?
There is no known exploitation of CVE-2022-50394 in the wild and no public exploit code.
Other vulnerabilities in Linux kernel
Sources
Also known as DEBIAN-CVE-2022-50394, GHSA-2wfh-xv6f-6623, UBUNTU-CVE-2022-50394.