CVE-2021-3546 Memory corruption in QEMU

What is CVE-2021-3546?

CVE-2021-3546 is a high-severity memory corruption vulnerability in Debian Debian Linux, published on 2 Jun 2021. It can only be exploited from the same machine or local network, with no action from the victim.

Official description

An out-of-bounds write 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 occurs while processing the 'VIRTIO_GPU_CMD_GET_CAPSET' command from the guest. It could allow a privileged guest user to crash the QEMU process on the host, resulting in a denial of service condition, or potential code execution with the privileges of the QEMU process.

Weakness: CWE-787

Which versions are affected by CVE-2021-3546?

It affects 2 products.

Products include Debian Debian Linux, Qemu Qemu.

How do I fix CVE-2021-3546?

Upgrade to a fixed version.

Upgrade to the fixed version. Memory-safe languages, compiler hardening and fuzzing prevent most new cases. More about Memory corruption.

Is CVE-2021-3546 being exploited?

There is no known exploitation of CVE-2021-3546 in the wild and no public exploit code.

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All Debian Debian Linux vulnerabilities

Sources

• CVE record
• NVD
• OSV
• GitHub advisory
• How this page is made

Also known as DEBIAN-CVE-2021-3546, GHSA-m53p-4wch-f983, UBUNTU-CVE-2021-3546.