medium CVSS 5.5

CVE-2023-52789·Kernel vulnerability

In the Linux kernel, the following vulnerability has been resolved: tty: vcc: Add check for kstrdup() in vcc_probe() Add check for the return value of kstrdup() and return the error, if it fails in order to avoid NULL pointer dereference.

Severity
medium
Software
Kernel
Fixed in
6.6.3
Published
2024-05-21

Affected versions

From: 6.6

Until: 6.6.3

Fixed in: 6.6.3

How to fix this CVE

Update your Linux kernel to version 6.6.3 or later to resolve a memory allocation handling issue in the tty vcc driver that could lead to system instability. The vulnerability occurs when the kernel fails to properly validate memory allocation during device probe operations, potentially resulting in a crash when the system attempts to access uninitialized memory.

sudo dnf update kernel

Defensia detects this vulnerability

How to check if you are affected

  1. Step 1: Check your current kernel version with `uname -r` and compare against 6.6.3
  2. Step 2: Verify the tty vcc module is loaded with `lsmod | grep vcc`
  3. Step 3: Search system logs for vcc-related probe failures using `dmesg | grep -i vcc` or `journalctl | grep -i vcc`
  4. Step 4: After applying the patch, reboot and confirm the new kernel version with `uname -r`, then verify no vcc probe errors appear in `dmesg`

FAQ

What is CVE-2023-52789?

This vulnerability is a missing null pointer check in the Linux kernel's tty vcc (virtual console controller) driver initialization. When memory allocation fails during device probe, the driver does not validate the failure, leading to potential null pointer dereference and denial of service.

Is CVE-2023-52789 being actively exploited?

No, this vulnerability is not listed in the CISA Known Exploited Vulnerabilities catalog and no public exploits are currently available. However, it should still be patched due to the denial of service impact.

What versions of Kernel are affected by CVE-2023-52789?

Kernel versions 6.6 through 6.6.2 are affected. Version 6.6.3 and all subsequent releases contain the fix.

How do I check if my server is vulnerable to CVE-2023-52789?

Run `uname -r` to display your kernel version. If the output is 6.6.0, 6.6.1, or 6.6.2, your system is vulnerable and requires immediate patching.

Does Defensia detect CVE-2023-52789?

Yes — Defensia's CVE advisory scanner compares installed package versions against the NVD database. If Kernel is installed on a monitored server, CVE-2023-52789 will appear in your dashboard with remediation steps.

Related Kernel CVEs

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References

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