Luanti 5 before 5.15.2, when LuaJIT is used, allows a Lua sandbox escape via a crafted mod.

published 2026-04-16 6 mo ago modified 2026-06-17 4 mo ago also EUVD-2026-23149

cvss: 9.3; version 3.1, CNA
cisa kev: Not listed; not in CISA's catalog
epss: 0.2%; EPSS 0.2% chance of exploitation in 30 days, percentile 7%
public exploits: 0; none known

Patch / fix

fixed in 1 distros 2 links 2

Luanti Luanti 5.15.2

debian ubuntu

luanti Debian 13 5.10.0+dfsg-5+deb13u1
luanti Debian 14 5.15.2+dfsg-1

debian advisories DEBIAN-CVE-2026-40959

luanti Ubuntu 25.10 5.10.0+dfsg-5+deb13u1build0.25.10.1
luanti Ubuntu 26.04 LTS 5.10.0+dfsg-5+deb13u1build0.26.04.1

ubuntu advisories UBUNTU-CVE-2026-40959

Ubuntu security data © Canonical Ltd., from https://github.com/canonical/ubuntu-security-notices via OSV; changed: normalised to fixed package versions per release. CC BY-SA 4.0

github.com/luanti-org/luanti@8a929df commit
github.com/luanti-org/luanti@53cef18 commit

Vendor advisories

What the vendors themselves say about their products: affected, fixed or not affected, and what to do.

red hat product security vex CVE-2026-40959 updated 2026-06-28 cvss 9.3

luanti: Luanti: Lua sandbox escape via crafted mod

Red Hat All currently supported Red Hat products
not affected: vulnerable code not present

Red Hat CSAF VEX © Red Hat, Inc., from https://security.access.redhat.com/data/csaf/v2/vex/; changed: reduced to product statuses and remediations. CC BY 4.0 · csaf

CISA SSVC

Exploitation: none
Automatable: no
Technical impact: total
Assessed: 6 mo ago (2026-04-16)

Exploit prediction

0.18% chance of exploitation in the next 30 days, higher than 7% of all scored CVEs (FIRST EPSS, 2026-11-08).

CVSS scores

assigned by	version	score	vector
CNA	3.1	9.3	CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:H

Affected products

Luanti Luanti

Classification

Weakness

CWE-829 Inclusion of Functionality from Untrusted Control Sphere

References

Sources

CVE List CVE-2026-40959
NVD CVE-2026-40959

Fencer Vulns keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.

Summary