Investigating third-party cloud synchronization tool abuse for data exfiltration

Threat actors use a wide variety of tools, including absolutely legitimate ones, to solve various tasks at different stages of the attack life cycle. Of course, the data exfiltration stage isn't an exception. We have already looked at web browsers and cloud service client application abuse for solving this task, but let's look at one more example.

Ransomware affiliates may want to be even stealthier to avoid detection and may leverage various masquerading techniques.

For example, they can rename tools to look like legitimate processes. As you already know, Shimcache is one of the most common sources of evidence of execution, so we can extract this data from the SYSTEM registry file (located under C:\Windows\System32\config), for example, via RegRipper, and check for any traces of leveraging masquerading.

Very soon, we notice the following record:

C:\Windows\svchost.exe 2021-12-26...