medium CVSS 5.5 EPSS <0.1%

CVE-2023-52806·Kernel vulnerability

In the Linux kernel, the following vulnerability has been resolved: ALSA: hda: Fix possible null-ptr-deref when assigning a stream While AudioDSP drivers assign streams exclusively of HOST or LINK type, nothing blocks a user to attempt to assign a COUPLED stream. As supplied substream instance may be a stub, what is the case when code-loading, such scenario ends with null-ptr-deref.

Severity
medium
Software
Kernel
Fixed in
6.6.3
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% — in the bottom 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.

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 null pointer dereference vulnerability in the ALSA HDA subsystem. This issue occurs when audio drivers attempt to assign incompatible COUPLED-type streams with stub substream instances, causing kernel crashes. Apply the patch immediately to prevent potential denial-of-service conditions on systems running affected kernel versions.

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 confirm if it falls between 6.6 and 6.6.2
  2. Step 2: Verify ALSA HDA driver is loaded by running `lsmod | grep snd_hda_intel`
  3. Step 3: Search kernel logs for audio DSP stream assignment errors using `sudo dmesg | grep -i 'hda\|alsa\|stream'`
  4. Step 4: After patching to 6.6.3+, reboot and confirm with `uname -r` that the new version is active

FAQ

What is CVE-2023-52806?

This vulnerability is a null pointer dereference in the Linux kernel's ALSA HDA audio subsystem that occurs when code attempts to assign a COUPLED stream type to a stub substream instance, triggering a kernel crash without proper validation.

Is CVE-2023-52806 being actively exploited?

No, this vulnerability is not listed in the CISA Known Exploited Vulnerabilities catalog and no public exploits are currently available.

What versions of Kernel are affected by CVE-2023-52806?

Linux kernel versions 6.6 through 6.6.2 are vulnerable; the fix is included in kernel 6.6.3 and later.

How do I check if my server is vulnerable to CVE-2023-52806?

Run `uname -r` to display your kernel version; if it shows 6.6, 6.6.1, or 6.6.2, your system is vulnerable.

Does Defensia detect CVE-2023-52806?

Yes — Defensia's CVE advisory scanner compares installed package versions against the NVD database. If Linux kernel is installed on a monitored server, CVE-2023-52806 will appear in your dashboard with remediation steps.

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References

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