Vulnerability in Marlinfirmware Marlin
CVE-2026-56111
Marlin Firmware through 2.1.2.7, fixed in commit 1f255d1, when built with MESH_BED_LEVELING enabled, contains an out-of-bounds write vulnerability in the M421 G-code handler that allows attackers to corrupt firmware memory by supplying out…
CVSS v3 metric
CVSS v3 base score 9.1 (Critical). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:H.
Affected products
- Marlinfirmware Marlin — versions 0, 1f255d16ec2d456454fd444494cfb338d62b0fa1
Weakness classification (CWE)
Public proof-of-concept exploits
References
- disclosure@vulncheck.com (technical-description, exploit)
- disclosure@vulncheck.com (issue-tracking)
- disclosure@vulncheck.com (patch)
- disclosure@vulncheck.com (third-party-advisory)
Frequently asked questions
- What is CVE-2026-56111?
- CVE-2026-56111 is a critical-severity vulnerability in Marlinfirmware Marlin, classified under Improper Validation of Array Index. CVSS score: 9.1/10. Published 2026-06-24.
- How severe is CVE-2026-56111?
- Critical severity. CVSS v3 base score is 9.1 out of 10.
- Is CVE-2026-56111 known to be exploited?
- 1 public proof-of-concept repositories are indexed. Not currently listed in the CISA KEV catalog.