CVE-2026-18686 GL.iNet CVE debrief

Who should care

Defenders responsible for GL.iNet GL-MT3000 devices, security teams, and vulnerability management teams should assess exposure and verify the effectiveness of current security controls. They should also monitor for potential exploitation attempts and plan for vendor-supported updates or mitigations.

Why it matters

The CVE-2026-18686 vulnerability in GL.iNet GL-MT3000 devices allows remote attackers to execute arbitrary commands, potentially leading to unauthorized access and control.

• Verify exposure of GL.iNet GL-MT3000 devices
• Assess the effectiveness of current security controls
• Monitor for potential exploitation attempts

Technical summary

The vulnerability is located in the nas-web RPC Wrapper of GL.iNet GL-MT3000 devices up to version 4.4.5. The function nas-web.add_user in the file /cgi-bin/glc is susceptible to command injection, allowing remote attackers to execute arbitrary commands. This could lead to unauthorized access and control of affected devices. Defenders should prioritize verifying exposure and assessing security controls for these devices. The CVE record provides details about the vulnerability, but additional information on affected versions and exploitation is needed.

Defensive priority

Defenders should prioritize verifying exposure of GL.iNet GL-MT3000 devices and assessing the effectiveness of current security controls.

Recommended defensive actions

• Verify exposure of GL.iNet GL-MT3000 devices
• Assess the effectiveness of current security controls
• Monitor for potential exploitation attempts
• Review compensating controls for exposed systems
• Check relevant monitoring, detection, and logs for exposed assets
• Track exceptions, retest remediated assets
• Plan vendor-supported updates or mitigations through normal change control

Evidence notes

The CVE record and NVD entry provide details about the vulnerability, but specific information on affected versions beyond 4.4.5 and verified exploitation is limited. Defenders should verify exposure and assess security controls for GL.iNet GL-MT3000 devices. The CVE record was published on 2026-08-04T00:16:40.520Z and has not been modified since then.

Sources and references

Methodology and review provenance

AI-assisted synthesis based on stored public vulnerability evidence. System validation, approval state, and publication status do not by themselves establish human review of this revision. PatchSiren helps prioritize defensive review and does not prove exposure or remediation on any system.