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
Published · last modified .
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.
EPSS exploit prediction
EPSS: 0.003 (23.2th percentile), scored .
Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 23rd percentile — 23.2% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.
EPSS over last 30 days · oldest: 0.003 · newest: 0.003 · change: 0.000
Affected products
- Qemu
- Debian Linux — versions 9.0, 10.0
- Red Hat Enterprise Linux — versions 8.0
- Qemu — versions up to, including qemu 4.2.0
Weakness classification (CWE)
References
- www.openwall.com/lists/oss-security/2021/02/05/1 (mailing-list, Patch, Mailing List, Third Party Advisory)
- lists.debian.org/debian-lts-announce/2021/02/msg00024.html (mailing-list, Mailing List, Third Party Advisory)
- bugzilla.redhat.com/show_bug.cgi (Patch, Third Party Advisory, Issue Tracking)
- security.netapp.com/advisory/ntap-20210708-0005/ (Third Party Advisory)
- lists.debian.org/debian-lts-announce/2022/09/msg00008.html (mailing-list, Mailing List, Third Party Advisory)
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.