CVE-2026-9401: Edimax BR-6675nD POST Request formWanTcpipSetup buffer overflow
A vulnerability has been found in Edimax BR-6675nD 1.12. Impacted is the function formWanTcpipSetup of the file /goform/formWanTcpipSetup of the component POST Request Handler. The manipulation of the argument pppUserName leads to buffer overflow. The attack can be initiated remotely. The exploit has been disclosed to the public and may be used. The vendor was contacted early about this disclosure but did not respond in any way.
Affected Software
Remediation
Recommended actions to resolve this vulnerability, in priority order.
- Configuration
Disable remote (WAN-side) management access on the device so configuration interfaces are not reachable from untrusted networks.
Edimax BR-6675nD (device management/administration) remote_management = disabled - Compensating control
At the network perimeter or host-based firewall/WAF, block or drop inbound HTTP/HTTPS POST requests targeting /goform/formWanTcpipSetup and restrict access to the device management interface to trusted IP ranges only.
- Operational
Monitor device and network logs for POST requests to /goform/formWanTcpipSetup and other suspicious activity; if exploitation is detected, isolate the affected device from the network and perform incident response (containment and forensic collection).
Event History
Frequently Asked Questions
What is the severity of CVE-2026-9401?
CVE-2026-9401 has a high severity rating of 8.8.
How does CVE-2026-9401 impact the Edimax BR-6675nD?
CVE-2026-9401 affects the formWanTcpipSetup function, allowing remote attackers to exploit a buffer overflow by manipulating the pppUserName argument.
What are the potential consequences of exploiting CVE-2026-9401?
Exploiting CVE-2026-9401 could lead to remote code execution and full system compromise.
How can I mitigate the risk of CVE-2026-9401?
To mitigate CVE-2026-9401, ensure that your Edimax BR-6675nD router is updated to the latest firmware version that addresses this vulnerability.
Is CVE-2026-9401 exploitable from outside the network?
Yes, CVE-2026-9401 can be exploited remotely, making it a significant security risk.