high CVSS 7 EPSS <0.1%

CVE-2023-52586·Kernel vulnerability

In the Linux kernel, the following vulnerability has been resolved: drm/msm/dpu: Add mutex lock in control vblank irq Add a mutex lock to control vblank irq to synchronize vblank enable/disable operations happening from different threads to prevent race conditions while registering/unregistering the vblank irq callback. v4: -Removed vblank_ctl_lock from dpu_encoder_virt, so it is only a parameter of dpu_encoder_phys. -Switch from atomic refcnt to a simple int counter as mutex has now been added v3: Mistakenly did not change wording in last version. It is done now. v2: Slightly changed wording of commit message Patchwork: https://patchwork.freedesktop.org/patch/571854/

Severity
high
Software
Kernel
Fixed in
6.7.4
Published

How likely is exploitation

FIRST's Exploit Prediction Scoring System puts the probability of this CVE being exploited in the next 30 days at <0.1% — higher than 1% of all published CVEs. EPSS is an independent forecast of exploitation, not a severity rating: it says nothing about how much damage a successful attack does, which is what a CVSS score measures.

Read the two together. CVE-2023-52586 scores 7 on CVSS, so a successful attack would be serious — but at <0.1%, almost nobody is currently attempting it. That is a different situation from a flaw under mass exploitation, and it is usually the difference between patching on your next maintenance window and patching tonight.

Affected versions

Until: 6.7.4

Fixed in: 6.7.4

How to fix this CVE

Update your Linux kernel to version 6.7.4 or later to resolve a race condition in the DRM/MSM/DPU display driver that could lead to privilege escalation. This vulnerability affects vblank interrupt handling and requires a kernel upgrade followed by a system reboot to take effect.

sudo dnf update kernel kernel-devel && sudo reboot

Defensia detects this vulnerability

How to check if you are affected

  1. Run 'uname -r' to display your current kernel version and compare it against version 6.7.4
  2. Check if the DRM/MSM/DPU driver is loaded by running 'lsmod | grep msm' or 'lsmod | grep dpu' on Qualcomm Snapdragon systems
  3. Search kernel logs for vblank-related errors using 'sudo dmesg | grep -i vblank' or 'sudo journalctl -k | grep -i vblank'
  4. Verify the patched kernel is running post-reboot by confirming 'uname -r' shows version 6.7.4 or newer

FAQ

What is CVE-2023-52586?

CVE-2023-52586 is a race condition vulnerability in the Linux kernel's DRM/MSM/DPU display subsystem where concurrent vblank interrupt enable/disable operations from multiple threads can fail to properly synchronize, potentially leading to code execution with elevated privileges.

Is CVE-2023-52586 being actively exploited?

No, CVE-2023-52586 is not currently included in CISA's Known Exploited Vulnerabilities catalog and no public exploits are available.

What versions of Kernel are affected by CVE-2023-52586?

All kernel versions prior to 6.7.4 are affected, particularly those running on Qualcomm Snapdragon systems with MSM display drivers enabled.

How do I check if my server is vulnerable to CVE-2023-52586?

Run 'uname -r' and compare the output to version 6.7.4; if your version is lower, you are vulnerable. Additionally, verify MSM display driver presence with 'lsmod | grep msm'.

Does Defensia detect CVE-2023-52586?

Yes — Defensia's CVE advisory scanner compares installed kernel versions against the NVD database. If a kernel version prior to 6.7.4 is installed on a monitored server, CVE-2023-52586 will appear in your dashboard with remediation steps.

Related Kernel CVEs

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References

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