What is CVE-2021-45464?

CVE-2021-45464 is a high-severity vulnerability in Kvmtool Project, classified under Out-of-bounds Write. CVSS score: 8.8/10. Published 2023-04-15.

How severe is CVE-2021-45464?

High severity. CVSS v3 base score is 8.8 out of 10.

Buffer overflow in Kvmtool Project

CVE-2021-45464

kvmtool through 39181fc allows an out-of-bounds write, related to virtio/balloon.c and virtio/pci.c. This allows a guest OS user to execute arbitrary code on the host machine.

Vulnerability class: Buffer Overflow

Published 2023-04-15 · last modified 2026-06-17.

CVSS v3 metric

CVSS v3 base score 8.8 (High). Vector: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H.

EPSS exploit prediction

EPSS: 0.004 (29.7th percentile), scored 2026-10-08.

Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 30th percentile — 29.7% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS over last 30 days · oldest: 0.004 · newest: 0.004 · change: -0.000

Affected products

Kvmtool Project

Weakness classification (CWE)

CWE-787 — Out-of-bounds Write

References

cdn.discordapp.com/attachments/921419715170164776/921882173517230100/exploit.c (Broken Link)
git.kernel.org/pub/scm/linux/kernel/git/will/kvmtool.git/log/ (Patch)
www.kalmarunionen.dk/writeups/2021/hxp-2021/lkvm/ (Exploit, Third Party Advisory)
git.kernel.org/pub/scm/linux/kernel/git/will/kvmtool.git/commit/ (Patch)

Frequently asked questions

What is CVE-2021-45464?: CVE-2021-45464 is a high-severity vulnerability in Kvmtool Project, classified under Out-of-bounds Write. CVSS score: 8.8/10. Published 2023-04-15.
How severe is CVE-2021-45464?: High severity. CVSS v3 base score is 8.8 out of 10.