CVE-2021-32847
Moby HyperKit uninitialized memory use in virtio-sock pci_vtsock_proc_tx
No known exploitation. EPSS puts it in the 28th percentile. A vendor fix is available.
What to do
The vendor has published a fix. Version details are below where the sources state them.
What it is
From the CVE record
HyperKit is a toolkit for embedding hypervisor capabilities in an application. In versions 0.20210107 and prior, a malicious guest can trigger a vulnerability in the host by abusing the disk driver that may lead to the disclosure of the host memory into the virtualized guest. This issue is fixed in commit cf60095a4d8c3cb2e182a14415467afd356e982f.
In plain language
No plain-language summary for this CVE yet.
Exploitation
Where each signal puts this CVE on the scale from published to confirmed exploited.
- CISA KEV
Not in the catalog. CISA has not confirmed exploitation.
- Public exploits
No public exploit or proof of concept found in the sources we track.
- EPSS
0.4% chance of exploitation activity in the next 30 days, which ranks it in the 28th percentile of scored CVEs.
Exploit Prediction Scoring System, FIRST.org. A probability, not a confirmation.
Lifecycle
5 events over 640 days, from the signal feeds we watch.
- Patch availablerecord updated
- Publishedweakness classified, att&ck mapped
Affected products
Technical detail
CVSS 3.1 vector
Open in the CVSS calculatorCVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:C/C:H/I:N/A:N
Scored 7.1 by NVD.
How it is reached
- Attack Vector LocalRequires local access to the vulnerable system (e.g. local login, malicious file)
- Attack Complexity LowNo special conditions — the attack can be reliably reproduced
- Privileges Required NoneNo authentication required — anyone can exploit this
- User Interaction NoneNo user interaction needed — fully automated exploitation
Scope
- Scope ChangedThe exploit can affect other components (e.g. sandbox escape, host compromise from VM)
Impact if exploited
- Confidentiality HighTotal information disclosure — all data in the component is compromised
- Integrity NoneNo integrity impact
- Availability NoneNo availability impact
Weaknesses
ATT&CK techniques
Mapped from the weaknesses above (CWE to ATT&CK), not observed in attacks.
Sources
References in the record
- securitylab.github.com/advisories/GHSL-2021-058-moby-hyperkit/
- github.com/moby/hyperkit/blob/2f061e447e1435cdf1b9eda364cea6414f2c606b/src/lib/pci_virtio_block.c
- github.com/moby/hyperkit/commit/cf60095a4d8c3cb2e182a14415467afd356e982f
And 2 more references. See all after sign-in
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