Red teamer @ Outflank, product owner Cobalt Strike/Outflank Security Tooling
Joined March 2018
- Tweets 112
- Following 146
- Followers 1,812
- Likes 95
12 Photos and videos
Jun 10
Hello world, hello CS 4.13!
Proud on the dev team, time for š„š
Jun 10
Cobalt Strike 4.13 is live! Say "Hello World" to our Beacon Interpreter for native C scripting - plus an LLVM Beacon, smoother docking UX, sharper payload management and more. Read about all the new features in the release blog!
cobaltstrike.com/blog/cobaltā¦
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Pieter Ceelen retweeted
Jun 10
Cobalt Strike 4.13 is live! Say "Hello World" to our Beacon Interpreter for native C scripting - plus an LLVM Beacon, smoother docking UX, sharper payload management and more. Read about all the new features in the release blog!
cobaltstrike.com/blog/cobaltā¦
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Jun 4
Yesterday I presented the @_CobaltStrike release party. Today at Orangecon to talk with @DaWouw about the evolution of post-ex.
Always nice to see other speakers recommend Cobalt Strike š
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Pieter Ceelen retweeted
May 22
Cobalt Strike 4.13 is about to drop and we're celebrating! You're cordially invited to our release party demo on June 3! Learn all about 4.13, which includes an overhaul of post-exploitation capabilities, reimagined red team workflows, and more. RSVP now:
register.gotowebinar.com/regā¦
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Pieter Ceelen retweeted
22 Dec 2025
With Cobalt Strike's new REST API, bold experimentation isn't just allowed, it's encouraged! Our latest blog provides a few examples to help inspire users to explore the way that #CobaltStrike and the generative AI ecosystem can be intertwined.
cobaltstrike.com/blog/me-mysā¦
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Pieter Ceelen retweeted
4 Dec 2025
Seeing is believing. Check out the video to see how version 4.12 makes #CobaltStrike sharper, smarter, and ready for the future. linoma.wistia.com/medias/9skā¦
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Pieter Ceelen retweeted
1 Dec 2025
One week after launch, we can finally REST! In our latest writeup, dive into the architecture of the REST API, get a walk-through, and learn about the features, including interacting with Python.
ow.ly/ae6V50XA7Bs
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Pieter Ceelen retweeted
24 Nov 2025
Cobalt Strike 4.12 is LIVE, complete with a new look for the GUI! Additionally, we're introducing:
- A REST API
- User Defined Command and Control (UDC2)
- New process injection options
- New UAC bypasses
- and more!
Check out the release blog for details.
ow.ly/RSmE50Xx1OS
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Pieter Ceelen retweeted
23 Oct 2025
20th OST release this year! Highlights of 2025 so far:āØ
-Hiding malware in secure enclaves
-New file formats for code exec, lateral and persistence
-Post-exploit tooling for Chromium
-Async BOFs & BOF-PE support
-Lots of evasion and tradecraft additions
ā¦ And much more to come!
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Pieter Ceelen retweeted
7 Oct 2025
curious about RL? learn to train an LLM with me in a couple weeks!
6 Oct 2025
Go beyond superficial usage of #LLMs and #AI in this free training from Cobalt Strike and Outflank experts. Gain practical experience to architect AI-powered attack chains and navigate AI assisted adversary simulation. Register now!
ow.ly/V5sC50X73i2
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7 Oct 2025
This one will be fun! Weāll show how you can integrate LLMs in various stages of red teaming via various hands-on assignments and practical examples. Hope to learn a bit myself as well š
6 Oct 2025
Go beyond superficial usage of #LLMs and #AI in this free training from Cobalt Strike and Outflank experts. Gain practical experience to architect AI-powered attack chains and navigate AI assisted adversary simulation. Register now!
ow.ly/V5sC50X73i2
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Pieter Ceelen retweeted
24 Sep 2025
Curious about Cobalt Strike? Well sharpen your digital pencils, as class is now in session with a brand new training course created by experts from Cobalt Strike and @_RastaMouse from @_ZeroPointSec, complete with guided labs!
ow.ly/e5og50X1GP0
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6 Aug 2025
Today 13:30 at the Fortra booth (#4422). I am talking about modern automation and LLM/MCP for Cobalt Strike 4.12
4 Aug 2025
Just packed my š§³for #BHUSA. Besides attending talks and hanging out there, doing a mini-talk at the Fortra Booth. Iāll show we hook LLM/AI into Cobalt Strike (CS 4.12 previewš«£); besides this lots of other content from @OutflankNL and @_CobaltStrike at Booth #4422
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4 Aug 2025
Just packed my š§³for #BHUSA. Besides attending talks and hanging out there, doing a mini-talk at the Fortra Booth. Iāll show we hook LLM/AI into Cobalt Strike (CS 4.12 previewš«£); besides this lots of other content from @OutflankNL and @_CobaltStrike at Booth #4422
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24 Jun 2025
I'm heading to #TROOPERS25 together with @HenriNurmi. Looking forward to great content and meeting people in person! Feel free to chat with us about Cobalt Strike, Outflank Security Tooling, roadmaps etc
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24 Jun 2025
I should be recognizable with a red @OutflankNL shirt and a @_CobaltStrike cap. It will be š and š„µ, so got a couple of Cobalt Strike caps š§¢ for give away!
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Pieter Ceelen retweeted
17 Mar 2025
Cobalt Strike 4.11 is out now! This release introduces a novel Sleepmask, a novel process injection technique, a new prepend reflective loader with new evasive options, asynchronous BOFs, DNS over HTTPs and more!
cobaltstrike.com/blog/cobaltā¦
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12 Mar 2025
Iām very happy with technical session earlier today. Content ranged from first time CS use to advanced customisation. and then a sneak peek into 4.11!
11 Mar 2025
Tomorrow: Don't miss a live technical tour of #cobalt strike with your expert guides, @ptrpieter and @0xTriboulet! Register now to see what our research team has brewing! #notliterally #cobaltstrikeguy #Cheers
register.gotowebinar.com/regā¦
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Pieter Ceelen retweeted
26 Feb 2025
Join us March 12 for a live technical walkthrough of #cobaltstrike's flexible framework and advanced post-exploitation techniques! Register now to see what our research team has cooking! #notliterally #cobaltstrikeguy
register.gotowebinar.com/regā¦
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Pieter Ceelen retweeted
3 Feb 2025
Virtual fortresses arenāt as invincible as they seem š°āļø.
Read about our latest research on using Secure Enclaves in Windows for offensive ops ā plus fresh insights for red teamers.
Check out Part 1 of our blog series here: outflank.nl/blog/2025/02/03/ā¦
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