medium CVSS 5.5

CVE-2021-47264·Kernel vulnerability

In the Linux kernel, the following vulnerability has been resolved: ASoC: core: Fix Null-point-dereference in fmt_single_name() Check the return value of devm_kstrdup() in case of Null-point-dereference.

Severity
medium
Software
Kernel
Fixed in
5.12.11
Published
2024-05-21

Affected versions

From: 5.11

Until: 5.12.11

Fixed in: 5.12.11

How to fix this CVE

Update your Linux kernel to version 5.12.11 or later to patch a null pointer dereference vulnerability in the ASoC audio subsystem's fmt_single_name() function. This vulnerability can cause a kernel panic when the audio core fails to allocate memory during device initialization. Apply the update immediately using your distribution's package manager.

sudo dnf update kernel kernel-devel

Defensia detects this vulnerability

How to check if you are affected

  1. Check your current kernel version: uname -r
  2. Verify if you are running a vulnerable version between 5.11 and 5.12.10 (inclusive)
  3. Check dmesg logs for audio subsystem initialization errors: dmesg | grep -i 'asoc\|audio' | grep -i 'error\|null'
  4. Confirm the patch is applied by checking if kernel version is 5.12.11 or later: uname -r | awk -F'.' '{if ($1==5 && $2==12 && $3>=11) print "Patched"; else print "Vulnerable"}'

FAQ

What is CVE-2021-47264?

CVE-2021-47264 is a null pointer dereference vulnerability in the Linux kernel's ASoC (ALSA System-on-Chip) audio driver core module. When the devm_kstrdup() memory allocation function fails during audio format name initialization, the kernel does not properly validate the return value, leading to a potential kernel crash.

Is CVE-2021-47264 being actively exploited?

No, CVE-2021-47264 is not listed in the CISA Known Exploited Vulnerabilities (KEV) catalog and no public exploits are known. However, denial-of-service impact remains possible on systems with constrained memory or specific audio hardware configurations.

What versions of Kernel are affected by CVE-2021-47264?

Linux kernel versions 5.11 through 5.12.10 are vulnerable. Version 5.12.11 and later contain the fix.

How do I check if my server is vulnerable to CVE-2021-47264?

Run 'uname -r' to check your kernel version. If the output shows a version between 5.11 and 5.12.10 inclusive, your system is vulnerable and requires an immediate kernel update.

Does Defensia detect CVE-2021-47264?

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-2021-47264 will appear in your dashboard with remediation steps.

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References

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