CVE-2021-4206 Integer overflow in QEMU

What is CVE-2021-4206?

CVE-2021-4206 is a high-severity vulnerability in Debian Debian Linux, published on 29 Apr 2022. It can only be exploited from the same machine or local network, with no action from the victim.

Official description

A flaw was found in the QXL display device emulation in QEMU. An integer overflow in the cursor_alloc() function can lead to the allocation of a small cursor object followed by a subsequent heap-based buffer overflow. This flaw allows a malicious privileged guest user to crash the QEMU process on the host or potentially execute arbitrary code within the context of the QEMU process.

Weakness: CWE-131, CWE-120, CWE-190

Which versions are affected by CVE-2021-4206?

It affects 3 products.

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

How do I fix CVE-2021-4206?

Apply the vendor's patch.

Is CVE-2021-4206 being exploited?

There is no known exploitation of CVE-2021-4206 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 AZL-35154, AZL-9618, DEBIAN-CVE-2021-4206, GHSA-rxh4-5vqx-xjq8, UBUNTU-CVE-2021-4206.