CVE-2026-40317: NovumOS has Privilege Escalation in the Syscall Interface

Severity: critical (CVSS 9.3 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 0.2% probability of exploitation in the next 30 days
Public exploit or detection template: yes
Published: 2026-04-18 · updated 2026-10-26
Weakness: CWE-20

Description

NovumOS is a custom 32-bit operating system written in Zig and x86 Assembly. In versions prior to 0.24, Syscall 12 (JumpToUser) accepts an arbitrary entry point address from user-space registers without validation, allowing any Ring 3 user-mode process to jump to kernel addresses and execute arbitrary code in Ring 0 context, resulting in local privilege escalation. This issue has been fixed in version 0.24. If developers are unable to immediately update, they should restrict syscall access by running the system in single-user mode without Ring 3, and disable user-mode processes by only running kernel shell with no user processes. This issue has been fixed in version 0.24.

Affected products

MinecAnton209 NovumOS: before 0.24 — fixed in 0.24

How to fix

Upgrade to a fixed version: MinecAnton209 NovumOS 0.24. Check the vendor advisory for mitigations.

References

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