NULL pointer dereference in moby hyperkit
Priority LOW 27CWE-476Published · Updated
Key facts
- Attack vector
- Local
- Privileges required
- None
- User interaction
- None
- Attack complexity
- Low
- Impact type
- Denial of service
- Confidentiality · integrity · availability
- None · None · High
- Fix status
- No fix listed
Attack profile from CVSS 3.1 · CNA. Fix status from CNA. Impact type from CWE-476.
Summary
HyperKit is a toolkit for embedding hypervisor capabilities in an application. In versions 0.20210107 and prior of HyperKit, `virtio.c` has is a call to `vc_cfgread` that does not check for null which when called makes the host crash. This issue may lead to a guest crashing the host causing a denial of service. This issue is fixed in commit df0e46c7dbfd81a957d85e449ba41b52f6f7beb4.
Why it matters now
Exploitation None reported CISA SSVC · not in CISA KEV
EPSS 0.00234 14th percentileScored 2026-11-07
Fix No fix listed No fixed version in the sources yet
SSVC decision points
CISA ADP · SSVC 2.0.3
- Exploitation
- None
- Automatable
- No
- Technical impact
- Partial
The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.
Affected products
| Vendor | Product | Affected versions | Fixed in | Status | Source |
|---|---|---|---|---|---|
| moby | hyperkit | 0.20210107 – 0.20210107 | — | No fix listed | CNA |
- hyperkit Vendormoby Affected 0.20210107 – 0.20210107 Fixed in — No fix listed CNA
CPE configurations NVD · 1
| CPE | Versions | Role | Vendor |
|---|---|---|---|
| cpe:2.3:a:mobyproject:hyperkit:*:*:*:*:*:*:*:* | up to 0.20210107 | Vulnerable | Mobyproject |
- cpe:2.3:a:mobyproject:hyperkit:*:*:*:*:*:*:*:* Versions up to 0.20210107 Vulnerable ·Mobyproject
Remediation
No fixed version listed by the sources yet.
Timeline
- 2026-10-02 Threatist record created from CVE-2021-32843
- 2026-10-03 Alias added: GHSA-x6m4-8q2v-7x97
References
More moby vulnerabilities
- TI-2026-14229 Tar extraction in moby/go-archive can write outside the destination directory via link following CVSS 4.0HIGH 7.1
- TI-2021-12512 Moby HyperKit uninitialized memory use in virtio-sock pci_vtsock_proc_tx CVSS 3.1HIGH 7.1
- TI-2024-27462 Moby authz zero length regression CVSS 3.1CRITICAL 10.0
- TI-2024-15672 BuildKit interactive containers API does not validate entitlements check CVSS 3.1CRITICAL 9.8
- TI-2024-15671 BuildKit possible host system access from mount stub cleaner CVSS 3.1CRITICAL 10.0
- TI-2026-26365 Moby: AuthZ plugin bypass with oversized request body CVSS 3.1HIGH 8.8
Sources
- CVE-2021-32843 · CVE Program
- CVE-2021-32843 · NVD
- FIRST EPSS
- GHSA-x6m4-8q2v-7x97 · GitHub Advisory Database · CC BY 4.0
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