Sebastian Forster

There's quite a discussion around #Signal and the recent phishing attacks in Germany. Let me highlight two of Signal's design choices that challenge a bit the gospel that victims of such attacks are just "too stupid".

1. Signal does send system information from time to time, for example to inform about new features. This looks like a standard message in a separate communication channel (i.e., a text message sent by "Signal"). I find it quite plausible that people will not always be able to distinguish such system messages from messages sent by other users having the Signal logo as their profile picture.

2. Although it is now often claimed that Signal would never ask for my PIN that's not true literally. It asks for my PIN from time to time to make sure I don't forget it. This request for entering the PIN appears as a pop up. But would a user being trained to have the app interact with them via text messages notice the difference between the pop up and a system message?

(Apart from that: There obviously were some not-so-smart moves by the involved people and institutions as well. I merely wanted to point out an aspect of the issue that I haven't seen discussed from the tech side so far.)

Our paper Incremental (k, z)-Clustering on Graphs got accepted to ICALP. This is joint work with Emilio Cruciani (who is now an assistant professor at the European University of Rome) and my former PhD student Antonis Skarlatos (who is a postdoc in Warwick now). Our group is working a lot on clustering algorithms tailored to graphs right now - mainly in the dynamic setting, but not exclusively.

Here's a link to the arXiv version: https://arxiv.org/abs/2602.08542

I have an open position for a predoctoral university assistant ("PhD student") in efficient graph algorithms. Our group has expertise in dynamic, distributed, and parallel algorithms. The position comes with a mild teaching load ("TAing").

Please find the official job description and the link to apply here: https://karriere.plus.ac.at/en/jobs/6e6aa798-0429-01e8-cabb-69c12151a2bd (Note that the gross salary listed there is for a hypothetical fulltime position, whereas the actual position is at 75% capacity, which is the standard for such positions at our university.)

The application deadline is May 6, 2026 and the expected start date is fall 2026. Don't hesitate to get in touch with me for informal inquiries or questions about the Austrian academic system.

#academicjobs #algorithms