CVE-2021-20203 Integer overflow in qemu

What is CVE-2021-20203?

CVE-2021-20203 is a low-severity vulnerability in Debian Debian Linux, published on 25 Feb 2021. It can only be exploited from the same machine or local network, with no action from the victim.

Official description

An integer overflow issue was found in the vmxnet3 NIC emulator of the QEMU for versions up to v5.2.0. It may occur if a guest was to supply invalid values for rx/tx queue size or other NIC parameters. A privileged guest user may use this flaw to crash the QEMU process on the host resulting in DoS scenario.

Weakness: CWE-190

Which versions are affected by CVE-2021-20203?

It affects 3 products.

Products include Debian Debian Linux, Fedoraproject Fedora, Qemu Qemu.

How do I fix CVE-2021-20203?

Upgrade to a fixed version.

Is CVE-2021-20203 being exploited?

There is no known exploitation of CVE-2021-20203 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-2021-20203, GHSA-8gqc-j7wm-6g58, UBUNTU-CVE-2021-20203.