Revisiting the UDRL Part 3: Beacon User Data
The UDRL and the Sleepmask are key components of Cobalt Strike’s evasion strategy, yet historically they have not worked well together. For example, prior to
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
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
User Defined Reflective Loader (UDRL) Update in Cobalt Strike 4.5
The User Defined Reflective Loader (UDRL) was first introduced in Cobalt Strike 4.4. to allow the creation and use of a custom reflective loader. This
Sleep Mask Update in Cobalt Strike 4.5
The Sleep Mask Kit was first introduced in Cobalt Strike 4.4 to allow users to modify how the sleep mask function looks in memory in order to defeat static signatures that identified Beacon. This
A Deeper Look Into the Max Retry Strategy Option
A complementary strategy to the Host Rotation Strategy was introduced to Cobalt Strike 4.5. The max retry strategy was added to HTTP, HTTPS, and DNS
Cobalt Strike DoS Vulnerability (CVE-2021-36798)
SentinelOne discovered a denial of service (DoS) vulnerability in Cobalt Strike. The bug (aka Hotcobalt) can cause a denial of service on a teamserver by using