medium CVSS 5.5

CVE-2024-40933·Kernel vulnerability

In the Linux kernel, the following vulnerability has been resolved: iio: temperature: mlx90635: Fix ERR_PTR dereference in mlx90635_probe() When devm_regmap_init_i2c() fails, regmap_ee could be error pointer, instead of checking for IS_ERR(regmap_ee), regmap is checked which looks like a copy paste error.

Severity
medium
Software
Kernel
Fixed in
6.9.6
Published
2024-07-12

Affected versions

From: 6.8

Until: 6.9.6

Fixed in: 6.9.6

How to fix this CVE

Update your Linux kernel to version 6.9.6 or later to resolve a pointer dereference bug in the MLX90635 temperature sensor driver. This vulnerability occurs when the regmap initialization fails but the error check is performed on the wrong variable, potentially causing a kernel panic. Systems running kernel versions 6.8 through 6.9.5 should prioritize this update to ensure stability of temperature monitoring hardware.

sudo dnf check-update kernel && sudo dnf update kernel

Defensia detects this vulnerability

How to check if you are affected

  1. Step 1: Check kernel version with `uname -r` and compare against 6.8-6.9.5 range to identify vulnerability exposure
  2. Step 2: Verify MLX90635 driver is loaded with `lsmod | grep mlx90635` or check `/sys/class/iio/` for temperature sensor devices
  3. Step 3: Search kernel logs for mlx90635 probe errors with `dmesg | grep -i mlx90635` or `journalctl -k | grep mlx90635`
  4. Step 4: Confirm kernel update applied by running `uname -r` and verifying version is 6.9.6 or later

FAQ

What is CVE-2024-40933?

CVE-2024-40933 is a pointer dereference vulnerability in the Linux kernel's MLX90635 temperature sensor driver. During device initialization, if the regmap fails to initialize, the error handling code checks the wrong variable, leading to a potential kernel panic or denial of service.

Is CVE-2024-40933 being actively exploited?

No, there is no evidence of active exploitation in the wild, and no public exploit code is available. This is primarily a stability issue affecting systems with MLX90635 temperature sensors.

What versions of Kernel are affected by CVE-2024-40933?

Linux kernel versions 6.8 through 6.9.5 are vulnerable. Kernel 6.9.6 and later versions include the fix.

How do I check if my server is vulnerable to CVE-2024-40933?

Run `uname -r` to check your kernel version. If it falls between 6.8 and 6.9.5, your system is vulnerable. Additionally, check if the MLX90635 driver is in use with `lsmod | grep mlx90635` or by inspecting `/sys/class/iio/` for temperature sensor devices.

Does Defensia detect CVE-2024-40933?

Yes — Defensia's CVE advisory scanner compares installed package versions against the NVD database. If the Linux kernel is installed on a monitored server, CVE-2024-40933 will appear in your dashboard with remediation steps.

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References

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