CVE-2021-3544 Memory corruption in QEMU

What is CVE-2021-3544?

CVE-2021-3544 is a medium-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

Several memory leaks were found in the virtio vhost-user GPU device (vhost-user-gpu) of QEMU in versions up to and including 6.0. They exist in contrib/vhost-user-gpu/vhost-user-gpu.c and contrib/vhost-user-gpu/virgl.c due to improper release of memory (i.e., free) after effective lifetime.

Weakness: CWE-401

Which versions are affected by CVE-2021-3544?

It affects 2 products.

Products include Debian Debian Linux, Qemu Qemu.

How do I fix CVE-2021-3544?

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-2021-3544 being exploited?

There is no known exploitation of CVE-2021-3544 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-2021-3544, GHSA-vx69-74f2-j536, UBUNTU-CVE-2021-3544.