357. That's Why I'm Talking About It That Often!

Hello everyone!

Today we'll look at an example provided by the colleagues from Zscaler in their recent research. And yes, it's legitimate services abuse one more time!

So, according to the research, Zscaler Threat Hunting observed a localized spike in traffic to the URL shortener surl[.]li. This service was used by the adversary (SideWinder) to redirect the victim to a phishing page with a link to gofile[.]io, which was used to host ZIP archives with a bunch of files, including malicious.

So, here we have a real-world example of how defenders leveraged the knowledge of legitimate web-services abused by adversaries to for a hypothesis and find undetected malicious activity.

You can do the same:

event_type: "dnsreqwin"

AND

dns_rname: ("surl.li" OR "gofile.io")

See you tomorrow!

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