medium CVSS 6.2 EPSS <0.1%

CVE-2023-52844·Kernel vulnerability

In the Linux kernel, the following vulnerability has been resolved: media: vidtv: psi: Add check for kstrdup 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
6.6.2
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 3% 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.

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 memory management flaw in the vidtv PSI module that could cause a denial of service. The vulnerability arises from insufficient validation of kernel memory allocation, allowing the kernel to proceed with null pointer operations if memory allocation fails. Apply this update promptly, particularly on systems running kernel versions 6.6 through 6.6.1.

sudo dnf update kernel kernel-devel

Defensia detects this vulnerability

How to check if you are affected

  1. Check your kernel version with: uname -r — if it shows 6.6.0, 6.6.1, or 6.6.2 (prior to patch), you may be vulnerable
  2. Verify the vidtv module is loaded: lsmod | grep vidtv — if output appears, the affected component is present
  3. Search kernel logs for PSI-related errors: dmesg | grep -i psi — look for allocation failures or null pointer warnings
  4. Confirm the fix was applied by rebooting and running uname -r again — it should show 6.6.2 or higher

FAQ

What is CVE-2023-52844?

This vulnerability is a missing null-pointer check in the Linux kernel's vidtv PSI (Program Specific Information) module. When the kstrdup() memory allocation function fails, the code does not validate the return value, leading to potential null pointer dereference and denial of service.

Is CVE-2023-52844 being actively exploited?

No — this vulnerability is not listed in CISA's Known Exploited Vulnerabilities catalog and no public exploits are currently available. However, the medium CVSS score (6.2) and local attack vector warrant timely patching.

What versions of Kernel are affected by CVE-2023-52844?

Linux kernel versions 6.6 through 6.6.1 are affected. The vulnerability was patched in kernel 6.6.2 and later releases.

How do I check if my server is vulnerable to CVE-2023-52844?

Run uname -r to display your kernel version. If it shows 6.6.0 or 6.6.1, your system is vulnerable. Additionally, verify the vidtv module is in use with: lsmod | grep vidtv

Does Defensia detect CVE-2023-52844?

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-2023-52844 will appear in your dashboard with remediation steps.

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References

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