What it is about

TeamViewer ist eine Fernzugriffs- und Fernsteuerungssoftware, die die Wartung von Computern und anderen Geräten ermöglicht. TeamViewer hat eine nicht näher spezifizierte Schwachstelle in seinem Clouddienst behoben. Diese betrifft die "out-of-session chat" Funktionalität des Full Client.

Under what conditions?

The BSI does not name any particular preconditions. Exploitable remotely according to the BSI.

Am I affected?

Affected according to the BSI:

• TeamViewer TeamViewer Full Client >=15.78
• TeamViewer TeamViewer Full Client <15.79.4

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

What helps?

Update to at least:

• TeamViewer TeamViewer Full Client >=15.78
• TeamViewer TeamViewer Full Client 15.79.4

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.