CVE-2021-2310

Hypervisor code execution via NAT buffer overflow

Published Apr 22, 2021 · Updated Sep 26, 2024

Heap-based buffer overflow in Oracle VM VirtualBox Core before 6.1.20 allows local users to execute code in the hypervisor through crafted NAT data. The NAT implementation copies user-supplied data into a fixed-length heap buffer without first validating its length. Exploitation requires high-privileged code execution in a guest and grants control of the hypervisor, potentially affecting other hosted systems.

CVSS severity7.5
High
EPSS probability0.65%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Heap-based buffer overflow in Oracle VM VirtualBox Core before 6.1.20 allows local users to execute code in the hypervisor through crafted NAT data. The NAT implementation copies user-supplied data into a fixed-length heap buffer without first validating its length. Exploitation requires high-privileged code execution in a guest and grants control of the hypervisor, potentially affecting other hosted systems.

The record

CVE
CVE-2021-2310
Published
Apr 22, 2021
Updated
Sep 26, 2024
Vendor
Oracle Corporation
Product
Oracle VM VirtualBox
Classifications
T1068
Attack vector
local
Privileges
admin

Timeline

How it unfolded

  1. Apr 22, 2021CVE publishedPublication date reported by the CVE source.
  2. Sep 26, 2024Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

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Is a vulnerable build present?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=unspecified <6.1.20

What conditions does exploitation require?

Attack vectorlocal
Required privilegesadmin

What is affected?

Oracle Corporation · Oracle VM VirtualBoxversion=unspecified <6.1.20

Published CVSS scores

7.5Oracle CorporationCVSS:3.1/AV:L/AC:H/PR:H/UI:N/S:C/C:H/I:H/A:H
4.4NIST NVDAV:L/AC:M/Au:N/C:P/I:P/A:P

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

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No observations available

Sep 10, 2026Sep 16, 2026
Latest reporting daySep 16, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectorlocal
Privilegesadmin
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

T1068Exploitation for Privilege Escalation

Public exploit references

No public exploit references are available in this record.

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Technologies

Your stack

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Your stack

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