VULNERABILITY INTELLIGENCE

CVE-2026-40317

CVSS score9.3 CRITICAL
EPSS probability0.22%
CISA KEVNot currently listed
Published2026-04-18
Last modified2026-10-26
CVSS vectorCVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:H

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.

Weakness classification

  • security-advisories@github.com: CWE-20

Primary references