CVE-2020-27821 Memory corruption in QEMU

What is CVE-2020-27821?

CVE-2020-27821 is a medium-severity memory corruption vulnerability in Debian Debian Linux, published on 8 Dec 2020. 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 memory management API of QEMU during the initialization of a memory region cache. This issue could lead to an out-of-bounds write access to the MSI-X table while performing MMIO operations. A guest user may abuse this flaw to crash the QEMU process on the host, resulting in a denial of service. This flaw affects QEMU versions prior to 5.2.0.

Weakness: CWE-787

Which versions are affected by CVE-2020-27821?

It affects 2 products.

Products include Debian Debian Linux, Qemu Qemu.

How do I fix CVE-2020-27821?

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-2020-27821 being exploited?

There is no known exploitation of CVE-2020-27821 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-2020-27821, GHSA-7p47-wfc3-mcqv, OESA-2021-1012, UBUNTU-CVE-2020-27821.