Zyxel security advisory for DNS misconfiguration in NBG7510 home router

Zyxel_May

CVE: CVE-2022-38546

Summary

Zyxel has released a patch addressing a DNS misconfiguration in the NBG7510 home router. Users are advised to install the applicable update for optimal protection.

What is the vulnerability?

A DNS misconfiguration in Zyxel’s NBG7510 could allow an unauthenticated attacker to perform DNS-related attacks, such as DNS tunneling or DNS amplification attacks, by using the open DNS resolver when the device is switched to the AP mode.

What versions are vulnerable—and what should you do?

After a thorough investigation, we’ve identified only one vulnerable product that is within the vulnerability support period and released a firmware patch to address the issue, as shown in the table below.

Affected model	Affected version	Patch availability
NBG7510	1.00(ABZY.2)C0 and earlier	V1.00(ABZY.3)C0

Got a question?

Please contact your local service rep or visit Zyxel’s Community for further information or assistance.

Acknowledgment

Thanks to Alexander Traud for reporting the issue to us.

Revision history

2022-12-21: Initial release.