---
cve: "CVE-2021-32846"
severity: "HIGH"
cvss: 7.7
epss: "32%"
vendor: "moby"
kev: false
exploited: false
published: "2023-02-17 23:15:12"
tags: [cve, security, high]
source: tsecurity.de CVE-Dossier
exported: "2026-09-13T05:28:11+02:00"
---

# CVE-2021-32846

> 7.7 HIGH · 🧪 PoC

## Beschreibung

HyperKit is a toolkit for embedding hypervisor capabilities in an application. In versions 0.20210107, function `pci_vtsock_proc_tx` in `virtio-sock` can lead to to uninitialized memory use. In this situation, there is a check for the return value to be less or equal to `VTSOCK_MAXSEGS`, but that check is not sufficient because the function can return `-1` if it finds an error it cannot recover from. Moreover, the negative return value will be used by `iovec_pull` in a while condition that can further lead to more corruption because the function is not designed to handle a negative `iov_len`. 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 af5eba2360a7351c08dfd9767d9be863a50ebaba.

## CVSS-Vektor

```
CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:H
```

| Metrik | Wert | Bewertung |
|---|---|---|
| AV Angriffsvektor | Lokal | good |
| AC Komplexität | Gering | bad |
| PR Privilegien | Keine | bad |
| UI Interaktion | Keine | bad |
| S Scope | Unverändert | good |
| C Vertraulichkeit | Keine | good |
| I Integrität | Hoch | bad |
| A Verfügbarkeit | Hoch | bad |

## Patch verfügbar (OSV)

- af5eba2360a7351c08dfd9767d9be863a50ebaba (Commit)

## Referenzen

- <https://securitylab.github.com/advisories/GHSL-2021-054_057-moby-hyperkit/>
- <https://github.com/moby/hyperkit/pull/313>
- <https://github.com/moby/hyperkit/commit/af5eba2360a7351c08dfd9767d9be863a50ebaba>

---
_Exportiert aus dem [tsecurity.de CVE-Dossier](https://tsecurity.de/cve?cve=CVE-2021-32846) · Datenquellen: EUVD (ENISA), NVD, OSV, CISA KEV, FIRST EPSS, Exploit-DB, BSI BITS_