CyberSecBulletin
CVE-2026-21956NVD status: Analyzed

Oracle VM VirtualBox: Uncontrolled Resource Consumption

CVE-2026-21956 is a high-severity uncontrolled resource consumption vulnerability in Oracle VM VirtualBox from Oracle, with a CVSS 3.1 base score of 8.2 out of 10. It can be exploited with local access to the system by an attacker with administrator privileges, without any action from a user. Affected Oracle VM VirtualBox versions: 7.1.14; 7.2.4. The record does not name a fixed version, so check the vendor advisory. There is no confirmed exploitation so far. EPSS estimates a 0.31% chance of exploitation within 30 days, which is low compared with other CVEs.

Next patch cycle

High severity with no evidence of exploitation so far.

What to do

  1. Check which version of Oracle VM VirtualBox you run against the affected versions below, and install the vendor's latest release.
  2. Read the advisory on oracle.com for workarounds and exact fixed builds.

Affected products and versions

VendorProductAffected versionsFixed in
OracleOracle VM VirtualBox7.1.14; 7.2.4Not stated
OracleVM Virtualbox7.1.14; 7.2.4Not stated

Version data comes from the organisation that assigned the CVE. Confirm against the vendor advisory before deciding you are unaffected.

How the severity score breaks down

Attack vector
LocalThe attacker needs local access or must trick a user into running something.
Attack complexity
LowNo special conditions are needed; the attack works reliably.
Privileges required
HighAdministrator-level access is required first.
User interaction
NoneNo action by a victim is required.
Scope
ChangedThe attack can reach beyond the vulnerable component into other systems.
Confidentiality
HighAll data handled by the component can be read.
Integrity
HighData or code can be modified at will.
Availability
HighThe component can be taken down completely.

Vector: CVSS:3.1/AV:L/AC:L/PR:H/UI:N/S:C/C:H/I:H/A:H. Scored by CNA (oracle.com).

Official description

Vulnerability in the Oracle VM VirtualBox product of Oracle Virtualization (component: Core). Supported versions that are affected are 7.1.14 and 7.2.4. Easily exploitable vulnerability allows high privileged attacker with logon to the infrastructure where Oracle VM VirtualBox executes to compromise Oracle VM VirtualBox. While the vulnerability is in Oracle VM VirtualBox, attacks may significantly impact additional products (scope change). Successful attacks of this vulnerability can result in takeover of Oracle VM VirtualBox. CVSS 3.1 Base Score 8.2 (Confidentiality, Integrity and Availability impacts). CVSS Vector: (CVSS:3.1/AV:L/AC:L/PR:H/UI:N/S:C/C:H/I:H/A:H).

Source: the CVE record as published by its numbering authority, via NVD and CVE.org.

The underlying weakness: Uncontrolled Resource Consumption

The product does not properly control the allocation and maintenance of a limited resource.

How developers prevent this class of flaw

  • Ensure that protocols have specific limits of scale placed on them.
  • Ensure that all failures in resource allocation place the system into a safe posture.

More Uncontrolled Resource Consumption vulnerabilities (CWE-400)

Timeline

  1. CVE record published.
  2. CISA published its SSVC assessment (exploitation: none, automatable: no, technical impact: total).
  3. Record last changed materially (score, affected products, status or references).

References

Other vulnerabilities in Oracle VM VirtualBox

All Oracle VM VirtualBox vulnerabilities

Recent Uncontrolled Resource Consumption vulnerabilities

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