SCRT Team Blog – Orange Cyberdefense Switzerland's technical 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.

Getting code execution on Veeam through CVE-2023-27532

While several blog posts have shown how to retrieve credentials through this vulnerability, we decided to dig deeper and see whether it was possible to execute arbitrary code through this issue.

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.

Insomni’hack 2024 – Bash to the Future writeup

The Challenge

You have been contracted to help COPERNIC Inc spot the light on a potential compromise. It seems that one of their scientists has been spied through a 20 years old malware… And fortunately, Zeus was on your side since the 4 Gb snapshot was carried out at the best possible time to facilitate your analysis.

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…

CVE-2022-41099 – Analysis of a BitLocker Drive Encryption Bypass

In November 2022, an advisory was published by Microsoft about a BitLocker bypass. This vulnerability caught my attention because the fix required a manual operation by users and system administrators, even after installing all the security updates. Couple this with the fact that the procedure was not well documented initially, and you have the perfect recipe for disaster.

This is typically the kind of vulnerability you do not want to deal with when you are in charge of a large fleet of workstations and laptops. However, on the other side of things, hard to patch vulnerabilities such as this one usually offer the best opportunities for red teamers and the like. This is where my journey investigating this bug and learning more about TPM-based BitLocker Drive Encryption began.