CVE-2021-45464
kvmtool through 39181fc allows an out-of-bounds write, related to virtio/balloon.c and virtio/pci...
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.
Attack profile
How easy it is to exploit
- Attack vector
- Local
- Complexity
- Low
- Privileges needed
- Low
- User interaction
- None
What an attacker can affect
- Confidentiality
- High
- Integrity
- High
- Availability
- High
Exploit likelihood
What each source reports
NVD Score used
8.8
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.
- Record
CVE-2021-45464- CVSS 3.1
- 8.8 High
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H - Weakness
- CWE-787
- Updated
- 2026-11-02
CVE List
8.8
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.
- Record
CVE-2021-45464- CVSS 3.1
- 8.8 High
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H - Weakness
- CWE-787
- Updated
- 2026-11-02
EUVDEUVD-2021-32230
8.8
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.
- Record
EUVD-2021-32230- CVSS 3.1
- 8.8 High
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H - Updated
- 2026-11-03
GitHub AdvisoriesGHSA-42pc-9g8v-prfm
8.8
kvmtool through 39181fc allows an out-of-bounds write, related to virtio/balloon.c and virtio/pci...
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.
- Record
GHSA-42pc-9g8v-prfm- CVSS 3.1
- 8.8 High
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H - Weakness
- CWE-787
- Updated
- 2026-11-02
OSVUBUNTU-CVE-2021-45464
8.8
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.
- Record
UBUNTU-CVE-2021-45464- CVSS 3.1
- 8.8 High
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H - Updated
- 2026-11-02
OSVUSN-8172-1 No score
kvmtool vulnerabilities
It was discovered that kvmtool did not properly manage memory under certain circumstances. A malicious guest attacker could use this issue to cause kvmtool to crash, leading to a denial of service, or possibly execute arbitrary code on the host system. (CVE-2021-45464)
It was discovered that kvmtool incorrectly handled the 9p passthrough file system. A malicious guest attacker could possibly use this issue to open special files, escape the exported 9p tree, and execute arbitrary code on the host system. (CVE-2023-2861)
- Record
USN-8172-1- Updated
- 2026-11-02
Affected products
Affected packages
| Package | Affected | Fixed |
|---|---|---|
kvmtoolUbuntu:Pro:16.04:LTS |
before 0.20151104-1ubuntu0.1~esm1, plus listed versions 0.20150908-10.20151104-1 |
0.20151104-1ubuntu0.1~esm1 |
kvmtoolUbuntu:Pro:18.04:LTS |
before 0.20170904-1ubuntu0.18.04.1~esm1, plus listed versions 0.20161128-10.20170904-1 |
0.20170904-1ubuntu0.18.04.1~esm1 |
kvmtoolUbuntu:Pro:20.04:LTS |
before 0.20170904-1ubuntu0.20.04.1~esm1, plus listed versions 0.20170904-1 |
0.20170904-1ubuntu0.20.04.1~esm1 |
kvmtoolUbuntu:Pro:22.04:LTS |
before 0.20170904-1.1ubuntu0.1~esm2, plus listed versions 0.20170904-1.1 |
0.20170904-1.1ubuntu0.1~esm2 |
History
| Recorded | Changed | Sources |
|---|---|---|
| aliases | EUVD | |
| first indexed | CVE List, GitHub Advisories, NVD, OSV |
Dates are when Every CVE recorded each change. Upstream dates may differ.
In short
CVE-2021-45464 is a high vulnerability (CVSS 8.8) in Kvmtool Project Kvmtool, published April 15, 2023. No source lists public exploit code. EPSS puts the chance of exploitation in the next 30 days at 0.38%, the 31st percentile. Fixed in kvmtool 0.20151104-1ubuntu0.1~esm1.
References
cdn.discordapp.com/attachments/921419715170164776/921882173517230100/exploit.c
git.kernel.org/pub/scm/linux/kernel/git/will/kvmtool.git/log
kalmarunionen.dk/writeups/2021/hxp-2021/lkvm
git.kernel.org/pub/scm/linux/kernel/git/will/kvmtool.git/commit?id=39181fc6429f4e9e71473284940e35857b42772a
nvd.nist.gov/vuln/detail/CVE-2021-45464
github.com/advisories/GHSA-42pc-9g8v-prfm