Control is a hard-rated box that required writing a shell through an SQL injection, using previously acquired hashes to pivote to a different user and then modifying a service to gain an Administrator shell.
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Recently the Qualys Research Team did an amazing job discovering a Heap overflow vulnerability in Sudo. In the next sections, we will analyze the bug and we will write an exploit to gain root privileges on Debain 10.
Rope2 by R4J has been my favorite box on HackTheBox by far. It wasn’t really related to pentesting, but was an immersive exploit dev experience