medium CVSS 5.5

CVE-2024-36956·Kernel vulnerability

In the Linux kernel, the following vulnerability has been resolved: thermal/debugfs: Free all thermal zone debug memory on zone removal Because thermal_debug_tz_remove() does not free all memory allocated for thermal zone diagnostics, some of that memory becomes unreachable after freeing the thermal zone's struct thermal_debugfs object. Address this by making thermal_debug_tz_remove() free all of the memory in question. Cc :6.8+ <stable@vger.kernel.org> # 6.8+

Severity
medium
Software
Kernel
Fixed in
6.8.10
Published
2024-05-30

Affected versions

From: 6.8

Until: 6.8.10

Fixed in: 6.8.10

How to fix this CVE

Update your Linux kernel to version 6.8.10 or later to address a memory leak in the thermal debugging subsystem. This vulnerability causes unreachable memory allocations when thermal zones are removed, potentially leading to denial of service over extended system operation. Apply the kernel update through your distribution's package manager and reboot to complete remediation.

sudo dnf update kernel && sudo reboot

Defensia detects this vulnerability

How to check if you are affected

  1. Check installed kernel version: uname -r | awk '{print $3}' to verify if it's below 6.8.10
  2. Confirm thermal debug subsystem is enabled: grep -i CONFIG_THERMAL_DEBUGFS /boot/config-$(uname -r) to check if the vulnerable component is active
  3. Search kernel logs for thermal zone removal events: dmesg | grep -i 'thermal.*remove\|thermal.*zone' to identify when thermal zones are being managed
  4. After patching, verify the new kernel is loaded: uname -r should show 6.8.10 or higher, confirming the update is active

FAQ

What is CVE-2024-36956?

This vulnerability is a memory leak in the Linux kernel's thermal debugging feature where the thermal_debug_tz_remove() function fails to properly deallocate all memory associated with thermal zone diagnostics, resulting in memory that becomes inaccessible and potentially exhausting system resources.

Is CVE-2024-36956 being actively exploited?

No, this vulnerability is not listed in the CISA KEV catalog and has no known public exploits. It is a local memory leak issue that requires kernel access to trigger.

What versions of Kernel are affected by CVE-2024-36956?

Linux kernel versions 6.8 through 6.8.9 are affected. Version 6.8.10 and later contain the fix.

How do I check if my server is vulnerable to CVE-2024-36956?

Run `uname -r` to display your kernel version. If it shows any version from 6.8 to 6.8.9, your system is vulnerable. Additionally, verify thermal debugging is enabled with `grep CONFIG_THERMAL_DEBUGFS /boot/config-$(uname -r)`.

Does Defensia detect CVE-2024-36956?

Yes — Defensia's CVE advisory scanner compares installed package versions against the NVD database. If Kernel is installed on a monitored server, CVE-2024-36956 will appear in your dashboard with remediation steps.

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References

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