CVE-2026-40959 Code injection in Luanti
Critical 9.3
Published
Updated
Check this codebase for CVE-2026-40959 and fix it if it is affected.
What it is: CVE-2026-40959 is a critical code injection vulnerability in Luanti, published on 16 Apr 2026. It can only be exploited from the same machine or local network, with no action from the victim.
Exploitation: There is no known exploitation of CVE-2026-40959 in the wild and no public exploit code.
Affected product: Luanti. No package-level version data is available, so check the vendor advisory linked from the reference page.
Task:
1. Search the dependency manifests and lockfiles (for example package.json, package-lock.json, requirements.txt, poetry.lock, uv.lock, pom.xml, build.gradle, go.mod, Cargo.lock, Gemfile.lock) and any Dockerfiles for the affected packages, including transitive dependencies.
2. If an affected version is in use, upgrade it to the fixed version for its release line with the project's package manager, so the lockfile is regenerated. Prefer the smallest upgrade that fixes it.
3. If there is no fix, or the upgrade would break the build, do not guess: explain the risk and the safest workaround instead.
4. Run the tests and summarise what changed and why.
5. If nothing in the project is affected, say so and change nothing.
Reference: https://insights.sbomify.com/CVE-2026-40959/ (Markdown: https://insights.sbomify.com/CVE-2026-40959/index.md)
Attackers can execute arbitrary code by exploiting a Lua sandbox escape in Luanti when LuaJIT is enabled via a crafted mod.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Local or same network only
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2026-40959?
CVE-2026-40959 is a critical code injection vulnerability in Luanti, published on 16 Apr 2026. It can only be exploited from the same machine or local network, with no action from the victim.
Official description
Luanti 5 before 5.15.2, when LuaJIT is used, allows a Lua sandbox escape via a crafted mod.
Weakness: CWE-829
Which versions are affected by CVE-2026-40959?
How do I fix CVE-2026-40959?
Upgrade to a fixed version.
Upgrade, and never evaluate templates, expressions or code built from user input. More about Code injection.
Is CVE-2026-40959 being exploited?
There is no known exploitation of CVE-2026-40959 in the wild and no public exploit code.
Sources
Also known as DEBIAN-CVE-2026-40959, GHSA-wxm2-x9x9-x5mj, UBUNTU-CVE-2026-40959.