How severe is CVE-2021-3736?

CVE-2021-3736 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 high, integrity none, and availability none.

Is CVE-2021-3736 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (15th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2021-3736?

CVE-2021-3736 affects Linux Linux Kernel. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2021-3736?

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

When was CVE-2021-3736 published?

CVE-2021-3736 was published on 2022-08-23 and last updated on 2026-06-17.

CVE-2021-3736

CVE-2021-3736 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-401.

Key facts

Severity: Medium (CVSS 3.x base score 5.5)
EPSS exploit prediction: 0% (15th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-401
Affected product: Linux Linux Kernel
Published: 2022-08-23
Last modified: 2026-06-17

Description

A flaw was found in the Linux kernel. A memory leak problem was found in mbochs_ioctl in samples/vfio-mdev/mbochs.c in Virtual Function I/O (VFIO) Mediated devices. This flaw could allow a local attacker to leak internal kernel information.

Frequently asked questions

What is CVE-2021-3736?: A flaw was found in the Linux kernel. A memory leak problem was found in mbochs_ioctl in samples/vfio-mdev/mbochs.c in Virtual Function I/O (VFIO) Mediated devices. This flaw could allow a local attacker to leak internal kernel information.
How severe is CVE-2021-3736?: CVE-2021-3736 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 high, integrity none, and availability none.
Is CVE-2021-3736 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (15th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2021-3736?: CVE-2021-3736 affects Linux Linux Kernel. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2021-3736?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2021-3736 published?: CVE-2021-3736 was published on 2022-08-23 and last updated on 2026-06-17.

References

Affected products (1)

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

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