Category Archives: Logging

PoC: Using KSQL to enrich Zeek logs with Osquery and Sysmon data

In incident response, time is precious and something you can never get back. Typically, when I receive a security alert about an endpoint, it requires manual lookups on multiple data sources for critical pieces of information. These manual lookups can be time-consuming, create fatigue, and don’t use the power of technology to your advantage. This blog post will demonstrate a proof-of-concept (POC) by using the power of a network community ID hash by Corelight to fuse endpoint and network-based data sources.

KSQL by Confluent provides the ability to enrich independent data sources by correlating common attributes. In this POC, we are going to use Sysmon or Osquery to monitor the endpoint and Zeek to monitor the network. Not only will this blog post serve as a POC but it will discuss the architecture, design decisions, working infrastructure-as-code, and the knowledge I accumulated from this project. The hope is that this POC will serve as a framework for the infosec community to use to perform log enrichment. Lastly, I will demonstrate the power of this POC by detecting a Powershell Empire agent that has been injected into explorer.exe.

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Generating CommunityIDs with Sysmon and Winlogbeat

While working on another logging project, I discovered a mechanism to generate CommunityIDs with Sysmon and Winlogbeat. Winlogbeat provides a feature called processors which can enrich log events before they are sent to the SIEM/logging server. This blog post will demonstrate a proof-of-concept (PoC) to enrich Sysmon network logs with a Community ID Network Flow Hash.

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Reducing your alert fatigue with AskJeevesSecBot

In incident response, there is a disconnect between a security alert being generated and a user’s confirmation of the security alert. For example, generating an alert every time a user runs “curl” on a production system would generate a bunch of false positives that can lead to what is called “alert fatigue”. But if we extend our incident response capabilities to include the user as part of the triage process we could reduce the number of alerts. This blog post is going to demonstrate AskJeevesSecBot which is an open-source proof of concept (POC) of how to integrate Slack and user responses into your security pipeline, specifically during the triage phase of the incident response process. In addition to a PoC, this blog post will also provide a deep dive into the architecture of this project, design decisions, and lessons learned as an evolving threat detection engineer.

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My logging pipeline: Splunk, Logstash, and Kafka

Over the years I have built several logging pipelines within my homelab and each used different technologies and methodologies but now I have finally built a pipeline that suites my needs. When I tell people about my pipeline they usually ask if I have a blog post on it because they want to know more or replicate it. This blog post is my attempt to share my logging pipeline as a framework for newcomers. The hope is that the explanation of the architecture, design decisions, working infrastructure-as-code, and the knowledge I accumulated over the years will be beneficial to the community. Continue reading

Creating my first Osquery extension to generate CommunityIDs with Osquery-python on Windows

Osquery is my favorite open-source security tool and Python is my favorite programming language so fusing them together allows us to engineer tools to detect threats. This blog post will build an Osquery-python extension to calculate the CommunityID of a network connection utilizing the Osquery-polylogyx extension pack to monitor network connections. In blog posts to follow, we will correlate network-based events generated by Zeek and host-based events generated by Osquery using the CommunityID. So follow me as your adventure guide on this development journey to make an Osquery extension with osquery-python.

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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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Back in the saddle: Install/Setup Elastic stack 7.0 on Ubuntu 18.04

Wow, the last time I really used the Elastic Stack it was called the ELK stack, and it was version 2.0. A lot of things have changed since then, so I am going to do an updated post on installing and setting up the Elastic stack.

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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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Part 1: Install/Setup Zeek + pf_ring on Ubuntu 18.04 on Proxmox 5.3 + openVswitch

 

Monitoring your home network can be challenging without enterprise-grade equipment. Although monitoring your home network can prove to be difficult, Proxmox and Zeek provide the perfect solution to monitor your home network. This blog post will cover how to setup Zeek+PF_Ring to monitor network traffic on Proxmox.

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Logging OSquery with Rsyslog v8 – Love at first sight

This blog post is going to cover how to ingest OSquery logs with Rsyslog v8. Most setups I have come across have Rsyslog ingesting the logs from disk, but this setup will ingest logs via the system journal. OSquery supports writing logs to disk and to the system journal. This post also contains a setup via Ansible and a manual walkthrough. Lastly, explanations of Rsyslog and OSquery configs.

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Install/Setup Graylog 3 on Ubuntu 18.04 – Zeeks logs + threat intel pipeline

 

Graylog has released version 3 with new features and major changes. This blog post will explain how to setup up Graylog version 3 on an Ubuntu server. Once Graylog is running, we will explore setting up logging clients, logging inputs, data extractors, threat intel pipelines, Slack alerts, dashboards and more.

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