Best Free Intrusion Detection and Prevention Systems of 2025

Empower your current team to achieve enterprise-level security All-in-one SIEM solution with endpoint visibility, 24/7 monitoring and automated response. Reduce complexity, increase visibility, and speed up response time. We do the heavy lifting so you can get back to your daily routine. Blumira's out-of-the box detections, prefiltered alerts and response playbooks can help IT teams achieve real security value. Quick Deployment and Immediate Results: Integrates into your tech stack, fully deploys in hours, without any warm-up period. All-You-Can-Eat: Predictable pricing, unlimited data logging and full-lifecycle detection. Compliance Made Easy - Includes 1 year data retention, pre-built reports and 24/7 automated monitoring 99.7% CSAT support: Solution Architects to support product support, Incident Detection and Response Team for new detections and 24/7 SecOps Support

Traditional packet filters are gradually becoming outdated, as even open-source solutions are shifting towards Next-Generation Firewalls. OPNsense stands out as a leading option for features like intrusion detection, application control, web filtering, and antivirus protection. No network, regardless of its size, is immune to potential attacks; even devices in home networks, such as washing machines and smartwatches, are at risk and need robust security measures. Firewalls play a crucial role in a comprehensive security strategy, shielding systems from both established and emerging threats. The effectiveness of a firewall is maximized when its capabilities are well understood, it operates intuitively, and is strategically placed within the network infrastructure. OPNsense rises to the occasion by fulfilling these essential requirements in various ways. This book serves as an invaluable guide for anyone looking to comprehend, install, and configure an OPNsense firewall effectively. Ultimately, understanding the intricacies of OPNsense can empower users to create a more secure digital environment.

A centralized management dashboard provides comprehensive visibility across the entire organization. All solutions within the technology stack are seamlessly integrated and communicate with a central database, enhancing efficiency in daily operations like monitoring, investigations, and incident response. The system employs both active and passive vulnerability scanners for early detection, along with pre-configured reports to assist in compliance audits. Users can effectively track and manage account access and changes in permissions, ensuring robust security measures are in place. Alerts are generated for any suspicious activities, allowing for timely intervention. Moreover, the dashboard enables remote management of the environment, facilitating prompt responses to potential attacks. It also includes a feature to monitor changes and access to sensitive information, ensuring that all classified data remains secure. Additionally, advanced threat protection safeguards endpoints and servers against emerging threats, creating a fortified security posture for the organization. Overall, this integrated approach not only streamlines processes but also significantly enhances the organization's ability to respond to and mitigate risks.

Enhance your security posture with LevelBlue USM Anywhere, a cutting-edge open XDR platform tailored to adapt to the dynamic nature of your IT environment and the increasing demands of your enterprise. Featuring advanced analytics, comprehensive security orchestration, and automation capabilities, USM Anywhere provides integrated threat intelligence that accelerates and sharpens threat detection while facilitating smoother response management. Its unparalleled flexibility is highlighted by a wide array of integrations, known as BlueApps, which improve its detection and orchestration capabilities across numerous third-party security and productivity applications. Additionally, these integrations allow for seamless triggering of automated and orchestrated responses, making security management more efficient. Take advantage of a 14-day free trial today to see how our platform can transform your approach to cybersecurity and help you stay ahead of potential threats.

The Suricata engine excels in real-time intrusion detection (IDS), inline intrusion prevention (IPS), network security monitoring (NSM), and offline packet capture (pcap) processing. It analyzes network traffic using a robust and comprehensive set of rules and signature languages, complemented by advanced Lua scripting capabilities that allow for the identification of intricate threats. Its compatibility with standard input and output formats such as YAML and JSON simplifies the integration with various tools, including established SIEMs, Splunk, Logstash/Elasticsearch, Kibana, and other databases. The development of Suricata is driven by a vibrant community focused on enhancing security, usability, and efficiency. Additionally, the project is managed and endorsed by the Open Information Security Foundation (OISF), a non-profit organization dedicated to fostering the ongoing development and success of Suricata as an open-source initiative. This commitment not only ensures the software's reliability but also actively encourages community contributions and collaboration.

OSSEC is completely open source and available at no cost, allowing users to customize its functionalities through a wide range of configuration settings, including the addition of personalized alert rules and the creation of scripts to respond to incidents as they arise. Atomic OSSEC enhances this capability by assisting organizations in fulfilling specific compliance standards like NIST and PCI DSS. It effectively identifies and notifies users of unauthorized alterations to the file system and any malicious activities that could jeopardize compliance. The Atomic OSSEC detection and response system, built on open-source principles, enriches OSSEC with thousands of advanced rules, real-time file integrity monitoring (FIM), regular updates, software integrations, built-in active response features, a user-friendly graphical interface (GUI), compliance resources, and dedicated professional support. This makes it a highly adaptable security solution that combines extended detection and response (XDR) with compliance capabilities in one comprehensive package. Its flexibility and thoroughness make it an invaluable tool for organizations aiming to bolster their security posture while maintaining compliance.

Protect your organization from credential-stuffing attacks and third-party data breaches. Hundreds of billions of records, including email addresses, user credentials, and passwords, have been breached. Hackers use these records to brute-force their way into organizations’ systems and networks to carry out targeted attacks. HEROIC EPIC is an Identity Breach Intelligence Platform™ that discovers and prevents credential stuffing and account takeover attacks

CrowdSec, a free, open-source, and collaborative IPS, analyzes behaviors, responds to attacks, and shares signals across the community. It outnumbers cybercriminals. Create your own intrusion detection system. To identify cyber threats, you can use behavior scenarios. You can share and benefit from a crowdsourced, curated cyber threat intelligence platform. Define the type and location of the remediation you wish to apply. Use the community's IP blocklist to automate your security. CrowdSec can be run on containers, virtual machines, bare metal servers, containers, or directly from your code using our API. Our cybersecurity community is destroying cybercriminals' anonymity. This is our strength. You can help us create and distribute a qualified IP blocklist that protects everyone by sharing IP addresses you have been annoyed by. CrowdSec can process massive amounts of logs faster than Fail2ban, and is 60x faster than Fail2ban.