CVE-2021-32845 json
Moby HyperKit uninitialized memory use vtrnd pci_vtrnd_notify
published 2023-02-17 3 y ago modified 2026-06-17 4 mo ago also EUVD-2021-19577
- cvss
- 7.7
- version 3.1, CNA
- cisa kev
- Not listed
- not in CISA's catalog
- epss
- 0.3%
- EPSS 0.3% chance of exploitation in 30 days, percentile 16%
- public exploits
- 0
- none known
Summary
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.
Patch / fix
- github.com/moby/hyperkit@41272a9 commit
- github.com/moby/hyperkit#313 pull request
CISA SSVC
- Exploitation
- none
- Automatable
- no
- Technical impact
- partial
- Assessed
- 19 mo ago
Exploit prediction
0.25% chance of exploitation in the next 30 days, higher than 16% of all scored CVEs (FIRST EPSS, 2026-11-08).
CVSS scores
| assigned by | version | score | vector |
|---|---|---|---|
| CNA | 3.1 | 7.7 | CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:H |
| NVD | 3.1 | 7.8 | CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H |
Affected products
- moby hyperkit
Classification
References
Sources
- CVE List CVE-2021-32845
- NVD CVE-2021-32845
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