CVE-2026-40317Public exploit

Local privilege escalation via unchecked syscall target

Published Apr 18, 2026 · Updated Apr 18, 2026

Privilege escalation in NovumOS before 0.24 allows local users to execute arbitrary code in Ring 0 through Syscall 12 (JumpToUser). The syscall handler in zig/user.zig accepts the EBX entry-point value from Ring 3 and jumps to it without verifying that it lies in user space. Any Ring 3 process can supply a kernel address, gaining kernel control over system data and execution.

CVSS severity9.3
Critical
EPSS probability0.22%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Privilege escalation in NovumOS before 0.24 allows local users to execute arbitrary code in Ring 0 through Syscall 12 (JumpToUser). The syscall handler in zig/user.zig accepts the EBX entry-point value from Ring 3 and jumps to it without verifying that it lies in user space. Any Ring 3 process can supply a kernel address, gaining kernel control over system data and execution.

The record

CVE
CVE-2026-40317
Published
Apr 18, 2026
Updated
Apr 18, 2026
Vendor
MinecAnton209
Product
NovumOS
Classifications
CWE-269, CWE-20, T1068
Attack vector
local
Privileges
authenticated

Timeline

How it unfolded

  1. Apr 18, 2026CVE publishedPublication date reported by the CVE source.
  2. Apr 18, 2026Record 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=< 0.24

What conditions does exploitation require?

Attack vectorlocal
Required privilegesauthenticated

What is affected?

MinecAnton209 · NovumOSversion=< 0.24

Published CVSS scores

9.3GitHub, Inc.CVSS:3.1/AV:L/AC:L/PR:N/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 exploitPublished

Weakness, pattern, technique

CWE-269Improper Privilege Management
CWE-20Improper Input Validation
T1068Exploitation for Privilege Escalation

Public exploit references

Labels summarize the accepted research assessment. They do not indicate a test against your environment.

Technologies

Your stack

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Your stack

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