high CVSS 7.8

CVE-2023-52624·Kernel vulnerability

In the Linux kernel, the following vulnerability has been resolved: drm/amd/display: Wake DMCUB before executing GPINT commands [Why] DMCUB can be in idle when we attempt to interface with the HW through the GPINT mailbox resulting in a system hang. [How] Add dc_wake_and_execute_gpint() to wrap the wake, execute, sleep sequence. If the GPINT executes successfully then DMCUB will be put back into sleep after the optional response is returned. It functions similar to the inbox command interface.

Severity: high
Software: Kernel
Fixed in: 6.7.3
Published: 2024-03-26

Affected versions

Until: 6.7.3

Fixed in: 6.7.3

How to fix this CVE

Update your Linux kernel to version 6.7.3 or later to resolve a display driver issue where DMCUB firmware may enter an idle state during GPU interface operations, causing system hangs. This fix ensures the display microcontroller is properly awakened before executing critical hardware commands. Apply the update immediately, particularly if you are using AMD display hardware.

sudo dnf update kernel kernel-devel

Defensia detects this vulnerability

How to check if you are affected

Run 'uname -r' to check the currently installed kernel version and verify it is 6.7.3 or later
Check if AMD display drivers are loaded using 'lsmod | grep amdgpu' or 'lsmod | grep amd'
Search kernel logs for system hangs or GPU communication timeouts: 'journalctl -b -p err | grep -i dmcub'
After patching, reboot and run 'uname -r' again to confirm the new kernel version is active; then monitor 'dmesg' for any DMCUB or display-related errors over the next 24 hours

FAQ

What is CVE-2023-52624?

CVE-2023-52624 is a kernel vulnerability affecting AMD display subsystem firmware where DMCUB (Display Microcontroller Unit Backup) can remain in an idle sleep state when GPU hardware commands are issued, leading to system hangs and loss of display functionality.

Is CVE-2023-52624 being actively exploited?

No, this vulnerability is not listed in the CISA Known Exploited Vulnerabilities catalog and no public exploits are available. However, it can be triggered through normal GPU operations on affected systems.

What versions of Kernel are affected by CVE-2023-52624?

Kernel versions prior to 6.7.3 are vulnerable. The exact initial affected version is not publicly documented, but all versions before 6.7.3 should be considered at risk if they contain the vulnerable display driver code.

How do I check if my server is vulnerable to CVE-2023-52624?

Run 'uname -r' to obtain your kernel version. If it returns a version earlier than 6.7.3 and you are using AMD display hardware (check with 'lspci | grep AMD'), your system is vulnerable and requires immediate patching.

Does Defensia detect CVE-2023-52624?

Yes — Defensia's CVE advisory scanner compares installed package versions against the NVD database. If Kernel is installed on a monitored server, CVE-2023-52624 will appear in your dashboard with remediation steps.

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References

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