What it is about

Zyxel ist ein Hersteller von Netzwerkkomponenten, u.a. von Firewalls. Ein entfernter, authentisierter Angreifer kann eine Schwachstelle in Zyxel Firewall ausnutzen, um beliebigen Programmcode auszuführen.

Under what conditions?

Over the network, but only with valid access (login required), for example with stolen credentials or as an insider.

What can happen in the worst case

An attacker could use the vulnerability to

• beliebigen Programmcode auszuführen

Am I affected?

Affected according to the BSI:

• Zyxel Firewall <5.43

The installed version is usually shown under “Help → About” or in the device’s admin interface.

What helps?

Update to at least:

• Zyxel Firewall 5.43

Is the vulnerability already being exploited?

None of the CVEs is in the CISA catalogue of exploited vulnerabilities. That does not mean there are no attacks, only that none are documented.