TeamViewer installs suspicious font only useful for web fingerprinting
The font is used by the teamviewer website. When inviting a partner to a teamviewer session, one can do so by sharing the invitation url.<p>The invitation url looks like this (where XXXXXXXX is the session code).<p><pre><code>  https://get.teamviewer.com/v15/en/sXXXXXXXX
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The website will check if a teamviewer font is installed (using javascript). If the font is found, the web site assumes that teamviewer is installed. The teamviewer installer also registers a protocol handler in the operating system.
The website (javascript code) will thus try to launch teamviewer directly using a url like the following:<p><pre><code>  teamviewer8://instantsupport/?sid=XXXXXXXX
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Otherwise, if the font is not found, it will prompt the user to download and install the teamviewer application.<p>Source:
Font detection routine:<p><pre><code>  https://get.teamviewer.com/get/res/scripts/fontdetect.js
</code></pre>
Connect routine:<p><pre><code>  https://get.teamviewer.com/get/res/scripts/connect.js</code></pre>