Category Archives: PoC

PoC: Mail.app the boomerang of reverse shells on macOS

This blog post is going to demonstrate a proof of concept (PoC) of sending an e-mail to trigger the Mail app (mail.app) to create a reverse shell. The Mail app has built-in functionality that can trigger an Applescript to execute code when certain conditions (new e-mail in inbox from bob, deletion of e-mail, or an e-mail containing certain text) occur within the Mail app. This functionality provides a method to initiate a reverse shell without user interaction or placing a persistent mechanism in a well-known location. The method below will utilize this functionality to monitor e-mails from a particular user, upon receiving an e-mail from said user, a reverse shell will call back to our Powershell Empire server.

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PoC: Exfiltrating data on macOS with Folder Actions

This blog post is going to demonstrate a proof of concept (PoC) to exfiltrate data from macOS with a built-in functionality called Folder Actions. The Folder Actions functionality triggers Applescripts to execute code when certain conditions (creating files, deleting files, etc.) occur by interactions with Finder. This functionality provides a method to exfiltrate data without the need for a shell to execute the actions. The Applescript provided below will utilize this functionality to monitor for new files in the user’s Download folder and, upon detection of a new file, exfiltrate a copy of the file to a remote server.

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PoC: Monitoring user browser activity with Osquery

This proof-of-concept (PoC) will demonstrate how to use Osquery to monitor the browser activity of users. Not only will this PoC collect browser activity, but it will also use VirusTotal to rank each URL to detect malicious activity. In addition to VirusTotal, this PoC will utilize Rsyslog, Osquery, Kafka, Splunk, Virustotal, Python3, and Docker as a logging pipeline. Once this pipeline has been implemented, your security team will have the ability to protect your user’s from today’s most serious threats on the web.

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Detecting malicious downloads with Osquery, Rsyslog, Kafka, Python3, and VirusTotal

This blog post will explore how to set up a simple logging pipeline to detect maliciously downloaded files. This setup will utilize technologies such as Osquery, Rsyslog, Kafka, Docker, Python3, and VirusTotal for a logging pipeline. If this pipeline detects a malicious file, a Slack alert will be triggered.

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Detecting SSH brute forcing with Zeek

In this blog post, we will explore how Zeek detects SSH brute forcing. We will explore the SSH handshake to understand how it works. Next, I will demonstrate several test cases of Zeek detecting SSH brute forcing. Finally, this post will lay down the foundation to implement active defense controls with Zeek in future posts.

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PoC: Using Cloudflare as an HTTP C2 with Powershell Empire

For a red teamer, one of the biggest challenges is utilizing a command-and-control(C2) server without being discovered and blocked. This is because the detected traffic is not coming from a trusted source. One way around this is to use CloudFlare’s free HTTP reverse proxy service as your C2. By pivoting all HTTP traffic through these proxies, it becomes much harder for a network defender to detect malicious intent.

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