What is CVE-2026-12187?

CVE-2026-12187 is a high-severity vulnerability in Gl.inet Gl-Mt3000, classified under Improper Neutralization of Special Elements in Output Used by a Downstream Component (Injection). CVSS score: 8.8/10. Published 2026-06-14.

How severe is CVE-2026-12187?

High severity. CVSS v3 base score is 8.8 out of 10.

RCE in Gl.inet Gl-Mt3000

CVE-2026-12187

A security vulnerability has been detected in GL.iNet GL-MT3000 up to 4.4.5. Affected by this vulnerability is an unknown functionality of the file /usr/bin/one_click_upgrade of the component Online Firmware Upgrade Handler. Such manipulation leads to command injection. The attack can be launched remotely. The exploit has been disclosed publicly and may be used. Upgrading to version 4.7 addresses this issue. Upgrading the affected component is advised. The vendor was contacted early, responded in a very professional manner and quickly released a fixed version of the affected product.

EPSS: 0.019 (79.0th percentile) — read the EPSS interpretation.

CVSS v3 metric

CVSS v3 base score 8.8 (High). Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H.

Affected products

Gl.inet Gl-mt3000 — versions 4.4.0, 4.4.1, 4.4.2

Weakness classification (CWE)

References

cna@vuldb.com (patch)
cna@vuldb.com (exploit, patch)
cna@vuldb.com (third-party-advisory)
cna@vuldb.com (third-party-advisory)
cna@vuldb.com (vdb-entry)
cna@vuldb.com (signature, permissions-required)

Frequently asked questions

What is CVE-2026-12187?: CVE-2026-12187 is a high-severity vulnerability in Gl.inet Gl-Mt3000, classified under Improper Neutralization of Special Elements in Output Used by a Downstream Component (Injection). CVSS score: 8.8/10. Published 2026-06-14.
How severe is CVE-2026-12187?: High severity. CVSS v3 base score is 8.8 out of 10.