Zyxel security advisory for LPE and authenticated directory traversal vulnerabilities of firewalls

Zyxel_May · July 2022

CVE: CVE-2022-30526, CVE-2022-2030

Summary

Zyxel has released patches for products affected by local privilege escalation (LPE) and authenticated directory traversal vulnerabilities. Users are advised to install them for optimal protection.

What are the vulnerabilities?

CVE-2022-30526

A privilege escalation vulnerability was identified in the CLI command of some firewall versions that could allow a local attacker to execute some OS commands with root privileges in some directories on a vulnerable device.

CVE-2022-2030

An authenticated directory traversal vulnerability caused by specific character sequences within an improperly sanitized URL was identified in some CGI programs of some firewall versions.

What versions are vulnerable-and what should you do?

After a thorough investigation, we’ve identified the vulnerable products for CVE-2022-30526 and CVE-2022-2030 that are within their vulnerability support period, with their firmware patches shown in the table below.

Affected model	Affected version		Patch availability
Affected model	CVE-2022-30526	CVE-2022-2030	Patch availability
USG FLEX 100(W), 200, 500, 700	ZLD V4.50~V5.30	ZLD V4.50~V5.30	ZLD V5.31
USG FLEX 50(W) / USG20(W)-VPN	ZLD V4.16~V5.30	ZLD V4.20~V5.30	ZLD V5.31
ATP series	ZLD V4.32~V5.30	ZLD V4.32~V5.30	ZLD V5.31
VPN series	ZLD V4.30~V5.30	ZLD V4.30~V5.30	ZLD V5.31
USG/ZyWALL	ZLD V4.09~V4.72	ZLD V4.20~V4.72	ZLD V4.72 week28

Got a question?

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

Acknowledgment

Thanks to the following security consultancies for reporting the issues to us:

Rapid7 for CVE-2022-30526
Maurizio Agazzini (HN Security) in collaboration with SSD Secure Disclosure for CVE-2022-2030

Revision history

2022-07-19: Initial release

2022-07-28: Updated the affected version of USG FLEX 50(W) / USG20(W)-VPN and USG/ZyWALL and added the patch download link for USG/ZyWALL

copossum · July 2022

Hi,

how would one go about getting a patch for a USG40 running 4.72(AALA.0)? How do I "reach out to my local Zyxel support team" fot the file?

I am in located in Europe/Austria.

or will a regular Firmware update be available shortly?

thank you

dkyeager · July 2022

This gets extremely tiring. While I am glad these exploits are being discovered and patched, I would rather have then uncovered before general release.