Research – SCRT Team Blog

Exploiting KsecDD through Server Silos

Earlier this year, an intriguing admin-to-kernel technique was published by @floesen_ in the form of a proof-of-concept (PoC) on GitHub. The author mentioned a strong limitation involving LSASS and Server Silos, without providing much details about it. This piqued our interest, so we decided to give it a second look…

Privilege escalation through TPM Sniffing when BitLocker PIN is enabled

This blog post offers additional insights following the presentation delivered at the Swiss Cyber Storm conference in Bern on October 22, 2024.

Ghost in the PPL Part 3: LSASS Memory Dump

Following my failed attempt to achieve arbitrary code execution within a protected LSASS process using the BYOVDLL technique and an N-day exploit in the KeyIso service, I took a step back, and ~~reconsidered my life choices~~ opted for a less ambitious solution: a (not so) simple memory dump. After all, when it comes to LSASS, we are mostly interested in extracting credentials stored in memory.

Ghost in the PPL Part 2: From BYOVDLL to Arbitrary Code Execution in LSASS

In the previous part, I showed how a technique called “Bring Your Own Vulnerable DLL” (BYOVDLL) could be used to reintroduce known vulnerabilities in LSASS, even when it’s protected. In this second part, I’m going to discuss the strategies I considered and explored to improve my proof-of-concept, and hopefully achieve arbitrary code execution.

Ghost in the PPL Part 1: BYOVDLL

In this series of blog posts, I will explore yet another avenue for bypassing LSA Protection in Userland. I will also detail the biggest challenges I faced while developing a proof-of-concept, and discuss some novel techniques and tricks to load an arbitrary DLL in LSASS, or even dump its memory.

Exploiting stale ADIDNS entries

The correct IP address is sometimes all you need to exploit a remote target.

A Deep Dive into TPM-based BitLocker Drive Encryption

When I investigated CVE-2022-41099, a BitLocker Drive Encryption bypass through the Windows Recovery Environment (WinRE), the fact that the latter was able to transparently access an encrypted drive without requiring the recovery password struck me. My initial thought was that there had to be a way to reproduce this behavior and obtain the master key from the Recovery Environment (WinRE). The outcome of a generic BitLocker bypass was too tempting not to explore this idea…

Bypassing PPL in Userland (again)

This post is a sequel to Bypassing LSA Protection in Userland and The End of PPLdump. Here, I will discuss how I was able to bypass the latest mitigation implemented by Microsoft and develop a new Userland exploit for injecting arbitrary code in a PPL with the highest signer type.