CVE-2021-47384 hwmon: (w83793) Fix NULL pointer dereference by removing unnecessary structure field
A NULL pointer dereference in the w83793 hardware monitoring driver allows attackers to cause a system crash via specific device inputs.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2021-47384?
CVE-2021-47384 is a medium-severity vulnerability in Linux kernel, published on 21 May 2024. 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:
hwmon: (w83793) Fix NULL pointer dereference by removing unnecessary structure field
If driver read tmp value sufficient for (tmp & 0x08) && (!(tmp & 0x80)) && ((tmp & 0x7) == ((tmp >> 4) & 0x7)) from device then Null pointer dereference occurs. (It is possible if tmp = 0b0xyz1xyz, where same literals mean same numbers) Also lm75[] does not serve a purpose anymore after switching to devm_i2c_new_dummy_device() in w83791d_detect_subclients().
The patch fixes possible NULL pointer dereference by removing lm75[].
Found by Linux Driver Verification project (linuxtesting.org).
[groeck: Dropped unnecessary continuation lines, fixed multi-line alignments]
Weakness: CWE-476
Which versions are affected by CVE-2021-47384?
It affects 1 product.
Products include Linux kernel.
How do I fix CVE-2021-47384?
Apply the vendor's patch.
Is CVE-2021-47384 being exploited?
There is no known exploitation of CVE-2021-47384 in the wild and no public exploit code.
Other vulnerabilities in Linux kernel
Sources
Also known as DEBIAN-CVE-2021-47384, GHSA-h6gr-4677-26p9, UBUNTU-CVE-2021-47384.