Revisiting the User-Defined Reflective Loader Part 2: Obfuscation and Masking

This is the second installment in a series revisiting the User-Defined Reflective Loader (UDRL). In part one, we aimed to simplify the development and debugging of custom loaders and introduced the User-Defined Reflective Loader Visual Studio (UDRL-VS) template. In this installment, we’ll build upon the original UDRL-VS loader and explore how to apply our own […]

Read More… from Revisiting the User-Defined Reflective Loader Part 2: Obfuscation and Masking

Cobalt Strike and YARA: Can I Have Your Signature?

Over the past few years, there has been a massive proliferation of YARA signatures for Beacon. We know from conversations with our customers that this has become problematic when using Cobalt Strike for red team engagements and that there has been some confusion over how Cobalt Strike’s malleable C2 options can help.   Therefore, this blog […]

Read More… from Cobalt Strike and YARA: Can I Have Your Signature?

Revisiting the User-Defined Reflective Loader Part 1: Simplifying Development

This blog post accompanies a new addition to the Arsenal Kit – The User-Defined Reflective Loader Visual Studio (UDRL-VS). Over the past few months, we have received a lot of feedback from our users that whilst the flexibility of the UDRL is great, there is not enough information/example code to get the most out of […]

Read More… from Revisiting the User-Defined Reflective Loader Part 1: Simplifying Development

Behind the Mask: Spoofing Call Stacks Dynamically with Timers

This blog introduces a PoC technique for spoofing call stacks using timers. Prior to our implant sleeping, we can queue up timers to overwrite its call stack with a fake one and then restore the original before resuming execution. Hence, in the same way we can mask memory belonging to our implant during sleep, we […]

Read More… from Behind the Mask: Spoofing Call Stacks Dynamically with Timers

Writing Beacon Object Files: Flexible, Stealthy, and Compatible

Our colleagues over at Core Security have been doing great things with Cobalt Strike, making use of it in their own engagements. They wrote up this post on creating Cobalt Strike Beacon Object Files using the MinGW compiler on Linux. It covers several ideas and best practices that will increase the quality of your BOFs. […]

Read More… from Writing Beacon Object Files: Flexible, Stealthy, and Compatible

Process Injection Update in Cobalt Strike 4.5

Process injection is a core component to Cobalt Strike post exploitation. Until now, the option was to use a built-in injection technique using fork&run. This has been great for stability, but does come at the cost of OPSEC. Cobalt Strike 4.5 now supports two new Aggressor Script hooks: PROCESS_INJECT_SPAWN and PROCESS_INJECT_EXPLICIT.  These hooks allow a user to define how the fork&run and explicit injection techniques are implemented when executing post-exploitation […]

Read More… from Process Injection Update in Cobalt Strike 4.5

Nanodump: A Red Team Approach to Minidumps

Motivation It is known that dumping Windows credentials is a technique often utilized for everyday attacks by adversaries and, consequently, Red Teamers. This process has been out there for several years and is well documented by MITRE under the T1003.001 technique. Sometimes, when conducting a Red Team engagement, there may be some limitations when trying […]

Read More… from Nanodump: A Red Team Approach to Minidumps

How to Extend Your Reach with Cobalt Strike 

We’re often asked, “what does Cobalt Strike do?” In simple terms, Cobalt Strike is a post-exploitation framework for adversary simulations and Red Teaming to help measure your security operations program and incident response capabilities. Cobalt Strike provides a post-exploitation agent, Beacon, and covert channels to emulate a quiet long-term embedded actor in a network.   If […]

Read More… from How to Extend Your Reach with Cobalt Strike 

CredBandit (In memory BOF MiniDump) – Tool review – Part 1

One of the things I find fascinating about being on the Cobalt Strike team is the community. It is amazing to see how people overcome unique challenges and push the tool in directions never considered. I want explore this with CredBandit (https://github.com/xforcered/CredBandit). This tool has had updates since I started exploring. I’m specifically, looking at […]

Read More… from CredBandit (In memory BOF MiniDump) – Tool review – Part 1