How severe is CVE-2021-47339?

CVE-2021-47339 has a CVSS 3.x base score of 5.5, rated medium severity. It is exploitable over local access with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is none, integrity none, and availability high.

Is CVE-2021-47339 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (14th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2021-47339?

CVE-2021-47339 affects Linux Linux Kernel. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2021-47339?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.

Does CVE-2021-47339 have an EU (EUVD) identifier?

Yes. CVE-2021-47339 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2021-34344.

When was CVE-2021-47339 published?

CVE-2021-47339 was published on 2024-05-21 and last updated on 2026-06-17.

CVE-2021-47339

CVE-2021-47339 is a medium-severity vulnerability in Linux Linux Kernel with a CVSS 3.x base score of 5.5. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-908.

Key facts

Severity: Medium (CVSS 3.x base score 5.5)
EPSS exploit prediction: 0% (14th percentile)
Actively exploited: Not listed in CISA KEV
EU (EUVD) id: EUVD-2021-34344
Weakness: CWE-908
Affected product: Linux Linux Kernel
Published: 2024-05-21
Last modified: 2026-06-17

Description

In the Linux kernel, the following vulnerability has been resolved: media: v4l2-core: explicitly clear ioctl input data As seen from a recent syzbot bug report, mistakes in the compat ioctl implementation can lead to uninitialized kernel stack data getting used as input for driver ioctl handlers. The reported bug is now fixed, but it's possible that other related bugs are still present or get added in the future. As the drivers need to check user input already, the possible impact is fairly low, but it might still cause an information leak. To be on the safe side, always clear the entire ioctl buffer before calling the conversion handler functions that are meant to initialize them.

Frequently asked questions

What is CVE-2021-47339?: In the Linux kernel, the following vulnerability has been resolved: media: v4l2-core: explicitly clear ioctl input data As seen from a recent syzbot bug report, mistakes in the compat ioctl implementation can lead to uninitialized kernel stack data getting used as input for driver ioctl handlers. The reported bug is now fixed, but it's possible that other related bugs are still present or get added in the future. As the drivers need to check user input already, the possible impact is fairly low, but it might still cause an information leak. To be on the safe side, always clear the entire ioctl buffer before calling the conversion handler functions that are meant to initialize them.
How severe is CVE-2021-47339?: CVE-2021-47339 has a CVSS 3.x base score of 5.5, rated medium severity. It is exploitable over local access with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is none, integrity none, and availability high.
Is CVE-2021-47339 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (14th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2021-47339?: CVE-2021-47339 affects Linux Linux Kernel. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2021-47339?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
Does CVE-2021-47339 have an EU (EUVD) identifier?: Yes. CVE-2021-47339 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2021-34344.
When was CVE-2021-47339 published?: CVE-2021-47339 was published on 2024-05-21 and last updated on 2026-06-17.

References

Affected products (1)

cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*

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