high CVSS 7.8

CVE-2023-52868·Kernel vulnerability

In the Linux kernel, the following vulnerability has been resolved: thermal: core: prevent potential string overflow The dev->id value comes from ida_alloc() so it's a number between zero and INT_MAX. If it's too high then these sprintf()s will overflow.

Severity
high
Software
Kernel
Fixed in
6.6.2
Published
2024-05-21

Affected versions

From: 6.6

Until: 6.6.2

Fixed in: 6.6.2

How to fix this CVE

Update your Linux kernel to version 6.6.2 or later to patch a buffer overflow vulnerability in the thermal management subsystem. The vulnerability exists in sprintf() calls within the thermal core module when device IDs exceed certain bounds, potentially allowing privilege escalation. Prioritize this update, especially for systems running kernel versions 6.6.0 through 6.6.2.

sudo dnf update kernel kernel-devel

Defensia detects this vulnerability

How to check if you are affected

  1. Check current kernel version: uname -r — confirm if version is between 6.6.0 and 6.6.2
  2. Verify thermal subsystem is loaded: lsmod | grep thermal — if output is empty, thermal module is not active and risk is lower
  3. Review kernel logs for thermal driver initialization errors: sudo dmesg | grep -i thermal — look for buffer overflows or sprintf-related warnings
  4. After patching, confirm new kernel version: uname -r — verify version is 6.6.2 or higher, then reboot if needed: sudo reboot

FAQ

What is CVE-2023-52868?

This vulnerability is a buffer overflow in the Linux kernel's thermal core module, where sprintf() calls can overflow when device IDs generated by ida_alloc() reach high values, potentially leading to memory corruption and privilege escalation from local unprivileged users.

Is CVE-2023-52868 being actively exploited?

No, this vulnerability is not listed on the CISA KEV catalog and has no public exploits available. However, the high CVSS score (7.8) and local privilege escalation potential warrant prompt patching.

What versions of Kernel are affected by CVE-2023-52868?

Linux kernel versions 6.6.0, 6.6.1, and 6.6.2 are affected. Version 6.6.2 introduced and resolved this issue. Older stable branches (6.5.x and earlier) and newer versions (6.7+) are not impacted.

How do I check if my server is vulnerable to CVE-2023-52868?

Run `uname -r` and check if the output shows a kernel version between 6.6.0 and 6.6.1. If you see 6.6.2 or higher, you are patched. Additionally, confirm thermal subsystem presence with `lsmod | grep thermal`.

Does Defensia detect CVE-2023-52868?

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-2023-52868 will appear in your dashboard with remediation steps.

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References

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