161. Adversaries Leverage DNS over HTTPS (DoH) to Evade Detection

Hello everyone!

Let's look at a curious example of Protocol Tunneling technique (T1572) as seen in a recent report by SentinelOne.

The adversary used a ShadowPad variant, which leveraged DNS over HTTPS (DoH) in an attempt to evade detection. In order to obscure DNS traffic, the threat actors Base-64 encoded queried domains, for example:

https://8.8.8.8:443/dns-query?dns=AAABAAABAAAAAAAABG5ld3MKaW1hZ2luZXJqcANjb20AAAEAAQ

So, if you have related telemetry - you know what to hunt for!

See you tomorrow!

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