CVE-2023-21987

Hypervisor code execution via TPM MMIO overflow

Published Apr 18, 2023 · Updated Sep 16, 2024

Stack-based buffer overflow in Oracle VM VirtualBox before 6.1.44 and before 7.0.8 allows local users to execute hypervisor code. The TPM MMIO handler copies a user-controlled length into a fixed-length stack buffer without validating that the input fits. Exploitation requires high-privileged code execution in a guest system and can cross the guest boundary to take over the hypervisor.

CVSS severity7.8
High
EPSS probability0.67%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Stack-based buffer overflow in Oracle VM VirtualBox before 6.1.44 and before 7.0.8 allows local users to execute hypervisor code. The TPM MMIO handler copies a user-controlled length into a fixed-length stack buffer without validating that the input fits. Exploitation requires high-privileged code execution in a guest system and can cross the guest boundary to take over the hypervisor.

The record

CVE
CVE-2023-21987
Published
Apr 18, 2023
Updated
Sep 16, 2024
Vendor
Oracle Corporation
Product
Oracle VM VirtualBox
Classifications
CWE-269, T1068
Attack vector
local
Privileges
authenticated

Timeline

How it unfolded

  1. Apr 18, 2023CVE publishedPublication date reported by the CVE source.
  2. Sep 16, 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?

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  1. Affected versionversion=* <6.1.44
  2. Affected versionversion=* <7.0.8

What conditions does exploitation require?

Attack vectorlocal
Required privilegesauthenticated

What is affected?

Oracle Corporation · Oracle VM VirtualBoxversion=* <6.1.44; version=* <7.0.8

Published CVSS scores

7.8OracleCVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:C/C:H/I:H/A:H
8.2Zero Day InitiativeCVSS:3.1/AV:L/AC:L/PR:H/UI:N/S:C/C:H/I:H/A:H
7.8NIST NVDCVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:C/C:H/I:H/A:H

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
Privilegesauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-269Improper Privilege Management
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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