Out-of-bounds Read in Qemu

CVE-2021-20221

An out-of-bounds heap buffer access issue was found in the ARM Generic Interrupt Controller emulator of QEMU up to and including qemu 4.2.0on aarch64 platform. The issue occurs because while writing an interrupt ID to the controller memory area, it is not masked to be 4 bits wide. It may lead to the said issue while updating controller state fields and their subsequent processing. A privileged guest user may use this flaw to crash the QEMU process on the host resulting in DoS scenario.

Vulnerability class: Buffer Overflow

EPSS: 0.003 (24.8th percentile) — read the EPSS interpretation.

CVSS v3 metric

CVSS v3 base score 6.0 (Medium). Vector: CVSS:3.1/AV:L/AC:L/PR:H/UI:N/S:C/C:N/I:N/A:H.

Affected products

Weakness classification (CWE)

References

Frequently asked questions

What is CVE-2021-20221?
CVE-2021-20221 is a medium-severity vulnerability in Qemu, classified under Out-of-bounds Read. CVSS score: 6.0/10. Published 2021-05-13.
How severe is CVE-2021-20221?
Medium severity. CVSS v3 base score is 6.0 out of 10.