How severe is CVE-2021-47657?

CVE-2021-47657 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-2021-47657 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (17th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2021-47657?

CVE-2021-47657 affects Linux Linux Kernel. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2021-47657?

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

Does CVE-2021-47657 have an EU (EUVD) identifier?

Yes. CVE-2021-47657 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2021-34648.

When was CVE-2021-47657 published?

CVE-2021-47657 was published on 2025-02-26 and last updated on 2026-06-17.

CVE-2021-47657

CVE-2021-47657 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-476.

Key facts

Severity: Medium (CVSS 3.x base score 5.5)
EPSS exploit prediction: 0% (17th percentile)
Actively exploited: Not listed in CISA KEV
EU (EUVD) id: EUVD-2021-34648
Weakness: CWE-476
Affected product: Linux Linux Kernel
Published: 2025-02-26
Last modified: 2026-06-17

Description

In the Linux kernel, the following vulnerability has been resolved: drm/virtio: Ensure that objs is not NULL in virtio_gpu_array_put_free() If virtio_gpu_object_shmem_init() fails (e.g. due to fault injection, as it happened in the bug report by syzbot), virtio_gpu_array_put_free() could be called with objs equal to NULL. Ensure that objs is not NULL in virtio_gpu_array_put_free(), or otherwise return from the function.

Frequently asked questions

What is CVE-2021-47657?: In the Linux kernel, the following vulnerability has been resolved: drm/virtio: Ensure that objs is not NULL in virtio_gpu_array_put_free() If virtio_gpu_object_shmem_init() fails (e.g. due to fault injection, as it happened in the bug report by syzbot), virtio_gpu_array_put_free() could be called with objs equal to NULL. Ensure that objs is not NULL in virtio_gpu_array_put_free(), or otherwise return from the function.
How severe is CVE-2021-47657?: CVE-2021-47657 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-2021-47657 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (17th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2021-47657?: CVE-2021-47657 affects Linux Linux Kernel. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2021-47657?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
Does CVE-2021-47657 have an EU (EUVD) identifier?: Yes. CVE-2021-47657 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2021-34648.
When was CVE-2021-47657 published?: CVE-2021-47657 was published on 2025-02-26 and last updated on 2026-06-17.

References

Affected products (1)

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

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