CVE-2021-3392 Use after free in QEMU

What is CVE-2021-3392?

CVE-2021-3392 is a low-severity use after free vulnerability in Debian Debian Linux, published on 23 Mar 2021. It can only be exploited from the same machine or local network, with no action from the victim.

Official description

A use-after-free flaw was found in the MegaRAID emulator of QEMU. This issue occurs while processing SCSI I/O requests in the case of an error mptsas_free_request() that does not dequeue the request object 'req' from a pending requests queue. This flaw allows a privileged guest user to crash the QEMU process on the host, resulting in a denial of service. Versions between 2.10.0 and 5.2.0 are potentially affected.

Weakness: CWE-416

Which versions are affected by CVE-2021-3392?

It affects 3 products.

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

How do I fix CVE-2021-3392?

Apply the vendor's patch.

Upgrade to the fixed version. These bugs are found with fuzzing and sanitisers and avoided by memory-safe languages. More about Use after free.

Is CVE-2021-3392 being exploited?

There is no known exploitation of CVE-2021-3392 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-2021-3392, GHSA-466h-jr37-234f, UBUNTU-CVE-2021-3392.