CyberSecBulletin
CVE-2026-40573NVD status: Deferred

NovumOS: Execution with Unnecessary Privileges

Published Updated By the CyberSecBulletin desk

CVE-2026-40573 is a high-severity execution with unnecessary privileges vulnerability in NovumOS from MinecAnton209, with a CVSS 3.1 base score of 8.6 out of 10. It can be exploited with local access to the system by an unauthenticated attacker, but only if a user takes part, for example by opening a link or file. Affected NovumOS versions: < 0.25-beta.1. The record does not name a fixed version, so check the vendor advisory. There is no confirmed exploitation so far. EPSS estimates a 0.13% 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 NovumOS you run against the affected versions below, and install the vendor's latest release.
  2. Read the advisory on github.com for workarounds and exact fixed builds.
  3. Because the attack needs a user to take part, warn users about unexpected links and files related to this product until it is patched.

Affected products and versions

VendorProductAffected versionsFixed in
MinecAnton209NovumOS< 0.25-beta.1Not 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
NoneNo account or login is needed.
User interaction
RequiredA user must take an action such as opening a file or link.
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:N/UI:R/S:C/C:H/I:H/A:H. Scored by CNA (github.com).

Official description

NovumOS is a custom 32-bit operating system written in Zig and x86 Assembly. Prior to version 0.25-beta.1, the `Nova` interpreter runs in Ring 0 with unrestricted kernel-memory access. Loading a malicious `.nv` script through the shell permits a local user to execute code with kernel privileges without security checks. The advisory identifies VM initialization in `zig/nova/vm.zig` as the affected component; script execution is not isolated in a restricted Ring 3 privilege domain. This issue is fixed in version 0.25-beta.1.

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

The underlying weakness: Execution with Unnecessary Privileges

The product performs an operation at a privilege level that is higher than the minimum level required, which creates new weaknesses or amplifies the consequences of other weaknesses.

How developers prevent this class of flaw

  • Run your code using the lowest privileges that are required to accomplish the necessary tasks. If possible, create isolated accounts with limited privileges that are only used for a single task. That way, a successful attack will not immediately give the attacker access to the rest of the software or its environment. For example, database applications rarely need to run as the database administrator, especially in day-to-day operations.
  • Identify the functionality that requires additional privileges, such as access to privileged operating system resources. Wrap and centralize this functionality if possible, and isolate the privileged code as much as possible from other code. Raise privileges as late as possible, and drop them as soon as possible to avoid CWE-271. Avoid weaknesses such as CWE-288 and CWE-420 by protecting all possible communication channels that could interact with the privileged code, such as a secondary socket that is only intended to be accessed by administrators.
  • Identify the functionality that requires additional privileges, such as access to privileged operating system resources. Wrap and centralize this functionality if possible, and isolate the privileged code as much as possible from other code. Raise privileges as late as possible, and drop them as soon as possible to avoid CWE-271. Avoid weaknesses such as CWE-288 and CWE-420 by protecting all possible communication channels that could interact with the privileged code, such as a secondary socket that is only intended to be accessed by administrators.

More Execution with Unnecessary Privileges vulnerabilities (CWE-250)

Timeline

  1. CVE record published.
  2. CISA published its SSVC assessment (exploitation: poc, automatable: no, technical impact: total).
  3. Record last changed materially (score, affected products, status or references).

References

Other vulnerabilities in NovumOS

All NovumOS vulnerabilities

Recent Execution with Unnecessary Privileges vulnerabilities

Spotted an error? Tell us.