CVE-2021-3507 Memory corruption in QEMU

What is CVE-2021-3507?

CVE-2021-3507 is a medium-severity memory corruption vulnerability in Debian Debian Linux, published on 6 May 2021. It can only be exploited from the same machine or local network, with no action from the victim.

Official description

A heap buffer overflow was found in the floppy disk emulator of QEMU up to 6.0.0 (including). It could occur in fdctrl_transfer_handler() in hw/block/fdc.c while processing DMA read data transfers from the floppy drive to the guest system. A privileged guest user could use this flaw to crash the QEMU process on the host resulting in DoS scenario, or potential information leakage from the host memory.

Weakness: CWE-787, CWE-119

Which versions are affected by CVE-2021-3507?

It affects 3 products.

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

How do I fix CVE-2021-3507?

Apply the vendor's patch.

Upgrade to the fixed version. Memory-safe languages, compiler hardening and fuzzing prevent most new cases. More about Memory corruption.

Is CVE-2021-3507 being exploited?

There is no known exploitation of CVE-2021-3507 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-2021-3507, GHSA-m99h-7jcp-j7w9, UBUNTU-CVE-2021-3507.