CVE-2026-46001 hwmon: (pt5161l) Fix bugs in pt5161l_read_block_data()
A buffer overflow in the Linux kernel pt5161l hardware monitoring driver allows attackers to cause memory corruption and potential code execution via malicious I2C responses.
- 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-2026-46001?
CVE-2026-46001 is a high-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:
hwmon: (pt5161l) Fix bugs in pt5161l_read_block_data()
Fix two bugs in pt5161l_read_block_data():
1. Buffer overrun: The local buffer rbuf is declared as u8 rbuf[24], but i2c_smbus_read_block_data() can return up to I2C_SMBUS_BLOCK_MAX (32) bytes. The i2c-core copies the data into the caller's buffer before the return value can be checked, so the post-read length validation does not prevent a stack overrun if a device returns more than 24 bytes. Resize the buffer to I2C_SMBUS_BLOCK_MAX.
2. Unexpected positive return on length mismatch: When all three retries are exhausted because the device returns data with an unexpected length, i2c_smbus_read_block_data() returns a positive byte count. The function returns this directly, and callers treat any non-negative return as success, processing stale or incomplete buffer contents. Return -EIO when retries are exhausted with a positive return value, preserving the negative error code on I2C failure.
Weakness: CWE-787
Which versions are affected by CVE-2026-46001?
It affects 1 product.
Products include Linux kernel.
How do I fix CVE-2026-46001?
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-2026-46001 being exploited?
There is no known exploitation of CVE-2026-46001 in the wild and no public exploit code.
Other vulnerabilities in Linux kernel
Sources
Also known as BELL-CVE-2026-46001, DEBIAN-CVE-2026-46001, GHSA-j98c-q2pf-9m22, UBUNTU-CVE-2026-46001.