How severe is CVE-2021-3545?

CVE-2021-3545 has a CVSS 3.x base score of 6.5, 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-2021-3545 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (34th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2021-3545?

CVE-2021-3545 primarily affects Qemu. In total, 2 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2021-3545?

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

When was CVE-2021-3545 published?

CVE-2021-3545 was published on 2021-06-02 and last updated on 2026-06-17.

CVE-2021-3545

CVE-2021-3545 is a medium-severity vulnerability in Qemu with a CVSS 3.x base score of 6.5. 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 6.5)
CVSS v2: 2.1
EPSS exploit prediction: 0% (34th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-908
Affected product: Qemu
Published: 2021-06-02
Last modified: 2026-06-17

Description

An information disclosure vulnerability was found in the virtio vhost-user GPU device (vhost-user-gpu) of QEMU in versions up to and including 6.0. The flaw exists in virgl_cmd_get_capset_info() in contrib/vhost-user-gpu/virgl.c and could occur due to the read of uninitialized memory. A malicious guest could exploit this issue to leak memory from the host.

Frequently asked questions

What is CVE-2021-3545?: An information disclosure vulnerability was found in the virtio vhost-user GPU device (vhost-user-gpu) of QEMU in versions up to and including 6.0. The flaw exists in virgl_cmd_get_capset_info() in contrib/vhost-user-gpu/virgl.c and could occur due to the read of uninitialized memory. A malicious guest could exploit this issue to leak memory from the host.
How severe is CVE-2021-3545?: CVE-2021-3545 has a CVSS 3.x base score of 6.5, 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-2021-3545 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (34th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2021-3545?: CVE-2021-3545 primarily affects Qemu. In total, 2 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2021-3545?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2021-3545 published?: CVE-2021-3545 was published on 2021-06-02 and last updated on 2026-06-17.

References

Affected products (2)

cpe:2.3:a:qemu:qemu:*:*:*:*:*:*:*:*
cpe:2.3:o:debian:debian_linux:11.0:*:*:*:*:*:*:*

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