CVE-2021-3416 Denial of service in QEMU

What is CVE-2021-3416?

CVE-2021-3416 is a medium-severity denial of service vulnerability in Debian Debian Linux, published on 18 Mar 2021. It can only be exploited from the same machine or local network, with no action from the victim.

Official description

A potential stack overflow via infinite loop issue was found in various NIC emulators of QEMU in versions up to and including 5.2.0. The issue occurs in loopback mode of a NIC wherein reentrant DMA checks get bypassed. A guest user/process may use this flaw to consume CPU cycles or crash the QEMU process on the host resulting in DoS scenario.

Weakness: CWE-835

Which versions are affected by CVE-2021-3416?

It affects 4 products.

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

How do I fix CVE-2021-3416?

Upgrade to a fixed version.

Upgrade, then put limits on request size, rate and nesting depth so one client cannot exhaust the service. More about Denial of service.

Is CVE-2021-3416 being exploited?

There is no known exploitation of CVE-2021-3416 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-2021-3416, GHSA-g3hx-jv57-3ffr, UBUNTU-CVE-2021-3416.