CVE-2026-41196: Critical Lua Sandbox Escape in Luanti (Minetest)

CVE-2026-41196 is a critical sandbox escape (CVSS 10.0) in Luanti, formerly Minetest. From version 5.0.0 until 5.15.2, a malicious mod can break out of the Lua sandbox and run code on the player's or server's machine. The fix is 5.15.2. Only LuaJIT builds are affected.

What's affected

Luanti from 5.0.0 and before 5.15.2. The advisory says the escape works in server-side mods, the async and mapgen environments, and the client-side mod (CSM) environment. It is only exploitable when Luanti uses LuaJIT, not plain PUC Lua.

How to check if you're exposed

The advisory gives the check directly. Run:

luanti --version

The output shows which kind of Lua your build uses. Compare the version with 5.15.2. Do this on game servers and on any client machines where players install mods from the in-game content browser or from the web.

The practical question is where your mods come from. A mod you wrote or audited is a very different risk from one pulled from an unknown author.

What to do now

1. Update Luanti to 5.15.2 or newer on servers and clients.
2. Until you can update, install only mods you trust, and disable client-side mods where you can.
3. If you cannot recompile, the advisory describes a workaround for release builds: edit builtin/init.lua and add getfenv = nil at the end. Note that this breaks mods that rely on that function.
4. If a server ran untrusted mods on an affected version, treat the host as potentially compromised and review it.

Why it matters

The record lists CWE-94, improper control of code generation. A sandbox is a promise that untrusted code stays inside a box. Here the box could be left with ordinary Lua, and the scope change in the CVSS vector reflects that a mod gains access well beyond the game.

Game mod ecosystems are a supply chain. Players install community code with very little review, and the host process often has the same rights as the user. A sandbox bug turns a mod download into a code execution event. The record does not flag this CVE as known exploited.

Quick check

Sources

• GitHub advisory GHSA-g596-mf82-w8c3

Last reviewed: 19 October 2026.