How severe is CVE-2021-47024?

CVE-2021-47024 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-2021-47024 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (16th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2021-47024?

CVE-2021-47024 affects Linux Linux Kernel. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2021-47024?

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

Does CVE-2021-47024 have an EU (EUVD) identifier?

Yes. CVE-2021-47024 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2021-33672.

When was CVE-2021-47024 published?

CVE-2021-47024 was published on 2024-02-28 and last updated on 2026-06-17.

CVE-2021-47024

CVE-2021-47024 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% (16th percentile)
Actively exploited: Not listed in CISA KEV
EU (EUVD) id: EUVD-2021-33672
Weakness: CWE-401
Affected product: Linux Linux Kernel
Published: 2024-02-28
Last modified: 2026-06-17

Description

In the Linux kernel, the following vulnerability has been resolved: vsock/virtio: free queued packets when closing socket As reported by syzbot [1], there is a memory leak while closing the socket. We partially solved this issue with commit ac03046ece2b ("vsock/virtio: free packets during the socket release"), but we forgot to drain the RX queue when the socket is definitely closed by the scheduled work. To avoid future issues, let's use the new virtio_transport_remove_sock() to drain the RX queue before removing the socket from the af_vsock lists calling vsock_remove_sock(). [1] https://syzkaller.appspot.com/bug?extid=24452624fc4c571eedd9

Frequently asked questions

What is CVE-2021-47024?: In the Linux kernel, the following vulnerability has been resolved: vsock/virtio: free queued packets when closing socket As reported by syzbot [1], there is a memory leak while closing the socket. We partially solved this issue with commit ac03046ece2b ("vsock/virtio: free packets during the socket release"), but we forgot to drain the RX queue when the socket is definitely closed by the scheduled work. To avoid future issues, let's use the new virtio_transport_remove_sock() to drain the RX queue before removing the socket from the af_vsock lists calling vsock_remove_sock(). [1] https://syzkaller.appspot.com/bug?extid=24452624fc4c571eedd9
How severe is CVE-2021-47024?: CVE-2021-47024 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-2021-47024 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (16th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2021-47024?: CVE-2021-47024 affects Linux Linux Kernel. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2021-47024?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
Does CVE-2021-47024 have an EU (EUVD) identifier?: Yes. CVE-2021-47024 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2021-33672.
When was CVE-2021-47024 published?: CVE-2021-47024 was published on 2024-02-28 and last updated on 2026-06-17.

References

Affected products (1)

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

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