CVE-2021-32845
Moby HyperKit uninitialized memory use vtrnd pci_vtrnd_notify
HyperKit is a toolkit for embedding hypervisor capabilities in an application. In versions 0.20210107 and prior of HyperKit, the implementation of qnotify at pci_vtrnd_notify fails to check the return value of vq_getchain. This leads to struct iovec iov; being uninitialized and used to read memory in len = (int) read(sc->vrsc_fd, iov.iov_base, iov.iov_len); when an attacker is able to make vq_getchain fail. This issue may lead to a guest crashing the host causing a denial of service and, under certain circumstance, memory corruption. This issue is fixed in commit 41272a980197917df8e58ff90642d14dec8fe948.
Attack profile
How easy it is to exploit
- Attack vector
- Local
- Complexity
- Low
- Privileges needed
- None
- User interaction
- None
What an attacker can affect
- Confidentiality
- None
- Integrity
- High
- Availability
- High
Exploit likelihood
What each source reports
CVE List Score used
Moby HyperKit uninitialized memory use vtrnd pci_vtrnd_notify
HyperKit is a toolkit for embedding hypervisor capabilities in an application. In versions 0.20210107 and prior of HyperKit, the implementation of qnotify at pci_vtrnd_notify fails to check the return value of vq_getchain. This leads to struct iovec iov; being uninitialized and used to read memory in len = (int) read(sc->vrsc_fd, iov.iov_base, iov.iov_len); when an attacker is able to make vq_getchain fail. This issue may lead to a guest crashing the host causing a denial of service and, under certain circumstance, memory corruption. This issue is fixed in commit 41272a980197917df8e58ff90642d14dec8fe948.
- Record
CVE-2021-32845- CVSS 3.1
- 7.7 High
CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:H - Weakness
- CWE-908
- Updated
- 2026-11-02
EUVDEUVD-2021-19577
HyperKit is a toolkit for embedding hypervisor capabilities in an application. In versions 0.20210107 and prior of HyperKit, the implementation of qnotify at pci_vtrnd_notify fails to check the return value of vq_getchain. This leads to struct iovec iov; being uninitialized and used to read memory in len = (int) read(sc->vrsc_fd, iov.iov_base, iov.iov_len); when an attacker is able to make vq_getchain fail. This issue may lead to a guest crashing the host causing a denial of service and, under certain circumstance, memory corruption. This issue is fixed in commit 41272a980197917df8e58ff90642d14dec8fe948.
- Record
EUVD-2021-19577- CVSS 3.1
- 7.7 High
CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:H - Updated
- 2026-11-02
GitHub AdvisoriesGHSA-hpc3-58qp-h295
HyperKit is a toolkit for embedding hypervisor capabilities in an application. In versions 0...
HyperKit is a toolkit for embedding hypervisor capabilities in an application. In versions 0.20210107 and prior of HyperKit, the implementation of qnotify at pci_vtrnd_notify fails to check the return value of vq_getchain. This leads to struct iovec iov; being uninitialized and used to read memory in len = (int) read(sc->vrsc_fd, iov.iov_base, iov.iov_len); when an attacker is able to make vq_getchain fail. This issue may lead to a guest crashing the host causing a denial of service and, under certain circumstance, memory corruption. This issue is fixed in commit 41272a980197917df8e58ff90642d14dec8fe948.
- Record
GHSA-hpc3-58qp-h295- CVSS 3.1
- 7.8 High
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H - Weakness
- CWE-252, CWE-908
- Updated
- 2026-11-02
NVD
HyperKit is a toolkit for embedding hypervisor capabilities in an application. In versions 0.20210107 and prior of HyperKit, the implementation of qnotify at pci_vtrnd_notify fails to check the return value of vq_getchain. This leads to struct iovec iov; being uninitialized and used to read memory in len = (int) read(sc->vrsc_fd, iov.iov_base, iov.iov_len); when an attacker is able to make vq_getchain fail. This issue may lead to a guest crashing the host causing a denial of service and, under certain circumstance, memory corruption. This issue is fixed in commit 41272a980197917df8e58ff90642d14dec8fe948.
- Record
CVE-2021-32845- CVSS 3.1
- 7.7 High
CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:H - CVSS 3.1
- 7.8 High
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H - Weakness
- CWE-908, CWE-252
- Updated
- 2026-11-02
OSV
HyperKit is a toolkit for embedding hypervisor capabilities in an application. In versions 0.20210107 and prior of HyperKit, the implementation of qnotify at pci_vtrnd_notify fails to check the return value of vq_getchain. This leads to struct iovec iov; being uninitialized and used to read memory in len = (int) read(sc->vrsc_fd, iov.iov_base, iov.iov_len); when an attacker is able to make vq_getchain fail. This issue may lead to a guest crashing the host causing a denial of service and, under certain circumstance, memory corruption. This issue is fixed in commit 41272a980197917df8e58ff90642d14dec8fe948.
- Record
CVE-2021-32845- CVSS 3.1
- 7.8 High
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H - Updated
- 2026-11-02
Affected products
History
| Recorded | Changed | Sources |
|---|---|---|
| first indexed | CVE List, EUVD, GitHub Advisories, NVD, OSV |
Dates are when Every CVE recorded each change. Upstream dates may differ.
In short
CVE-2021-32845 is a high vulnerability (CVSS 7.7) in Moby Hyperkit, published February 17, 2023. No source lists public exploit code. EPSS puts the chance of exploitation in the next 30 days at 0.25%, the 16th percentile. No source names a fixed version.