CVE-2026-36603

Mercusys AC12G (EU) V1 router with firmware AC12G(EU)_V1_200909 exposes 15 of 18 UPnP IGD actions without authentication on port 1900, including AddPortMapping and GetExternalIPAddress. UPnP is enabled by default through the admin interface, allowing any unauthenticated LAN device to create arbitrary port forwarding rules and access WAN traffic statistics.

CVSS v3 8.1 HIGH

8.1^/10

CVSS v3 : HIGH

Vector :

Exploitability : 2.8 / Impact : 5.2

Attack Vector ADJACENT_NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact HIGH

Integrity Impact HIGH

Availability Impact NONE

Scope UNCHANGED

References

Link	Resource
https://github.com/Tymbark7372/MERCUSYS-AC12G/blob/master/advisories/CVE-2026-36603.md

Configurations

No configuration.

History

No history.

Information

Published : 2026-06-03 18:16

Updated : 2026-07-22 19:10

NVD link : CVE-2026-36603

Mitre link : CVE-2026-36603

CVE.ORG link : CVE-2026-36603

JSON object : View

Products Affected

No product.

CWE

CWE-306

Missing Authentication for Critical Function

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