Security Advisory: DrayTek Router unauthenticated remote code execution vulnerability (CVE-2022-32548)

Action Required: Check firmware version on units and upgrade if required

In April 2022, DrayTek became aware of a possible exploit affecting some of their products that was identified during testing and reported to them*. DrayTek are not aware of any exploits of this in the wild and started to release firmware updates in May 2022. DrayTek’s standard best practice recommendation is to always keep firmware up to date, but recommend that you check that affected units are running at least the firmware version in the table below. If the model is not listed, then it is not affected by this vulnerability. To protect users until all firmware versions were available and to give time for upgrades, no other information about the issue was released originally. The vulnerability has now been announced under CVE-2022-32548 and is related to a possible exploit of the router’s Web UI login page.

1. If you have not already upgraded, update your firmware immediately. Before doing the upgrade, take a backup of your current config in case you need to restore it later (system maintenance -> Config Backup). Do use the .ALL file to upgrade, otherwise you will wipe your router settings. If you are upgrading from a much older firmware then please check the release notes carefully for any upgrading instructions.

2. If you have remote access enabled on your router, disable it if you don’t need it, and use an access control list and 2FA if possible. If your unit is not already running patched firmware (see table below), disable remote access (admin) and SSL VPN. The ACL does not apply to SSL VPN connections (Port 443) so you should also temporarily disable SSL VPN until you have updated the firmware.

3. It is good practice to update the router admin password.