medium CVSS 6.2

CVE-2023-52861·Kernel vulnerability

In the Linux kernel, the following vulnerability has been resolved: drm: bridge: it66121: Fix invalid connector dereference Fix the NULL pointer dereference when no monitor is connected, and the sound card is opened from userspace. Instead return an empty buffer (of zeroes) as the EDID information to the sound framework if there is no connector attached.

Severity
medium
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 resolve this audio subsystem stability issue. The vulnerability occurs when the DRM bridge driver attempts to access display connector information without proper validation, causing a crash when audio applications query EDID data on systems with no monitor connected. Applying this kernel update will add proper null-pointer checks to prevent the kernel panic.

sudo dnf update kernel kernel-devel

Defensia detects this vulnerability

How to check if you are affected

  1. Check current kernel version: uname -r (vulnerable if output shows 6.6.0, 6.6.1, or 6.6.2 without the patch)
  2. Verify if DRM bridge driver is loaded: lsmod | grep it66121 (confirms the vulnerable component is active)
  3. Search kernel logs for NULL pointer dereference errors: dmesg | grep -i 'null pointer\|it66121\|drm.*bridge' (look for recent crashes related to audio or EDID)
  4. Confirm the fix by checking the kernel version post-update: uname -r (should show 6.6.2 or later, or a distribution kernel with the backported fix)

FAQ

What is CVE-2023-52861?

A kernel null pointer dereference in the it66121 DRM bridge driver that crashes the system when audio applications request display connector information on headless systems (systems without monitors).

Is CVE-2023-52861 being actively exploited?

No, this vulnerability is not listed in the CISA Known Exploited Vulnerabilities (KEV) catalog and has no public exploits available. It requires local system access and specific hardware/software conditions to trigger.

What versions of Kernel are affected by CVE-2023-52861?

Linux kernel versions 6.6.0 through 6.6.2 are vulnerable. The fix was released in kernel 6.6.2.

How do I check if my server is vulnerable to CVE-2023-52861?

Run 'uname -r' to get your kernel version. If it shows 6.6.0, 6.6.1, or 6.6.2 without a distribution patch identifier, verify the vulnerability is present by checking if lsmod | grep it66121 returns results and your system has audio devices configured.

Does Defensia detect CVE-2023-52861?

Yes — Defensia's CVE advisory scanner compares installed package versions against the NVD database. If Kernel is installed on a monitored server, CVE-2023-52861 will appear in your dashboard with remediation steps.

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References

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