CVE-2021-3713 Memory corruption in QEMU

What is CVE-2021-3713?

CVE-2021-3713 is a high-severity memory corruption vulnerability in Debian Debian Linux, published on 25 Aug 2021. It can only be exploited from the same machine or local network, with no action from the victim.

Official description

An out-of-bounds write flaw was found in the UAS (USB Attached SCSI) device emulation of QEMU in versions prior to 6.2.0-rc0. The device uses the guest supplied stream number unchecked, which can lead to out-of-bounds access to the UASDevice->data3 and UASDevice->status3 fields. A malicious guest user could use this flaw to crash QEMU or potentially achieve code execution with the privileges of the QEMU process on the host.

Weakness: CWE-787

Which versions are affected by CVE-2021-3713?

It affects 2 products.

Products include Debian Debian Linux, Qemu Qemu.

How do I fix CVE-2021-3713?

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-2021-3713 being exploited?

There is no known exploitation of CVE-2021-3713 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-6831, DEBIAN-CVE-2021-3713, GHSA-q4w6-2g7p-pr2c, OESA-2021-1348, UBUNTU-CVE-2021-3713.