10 Best Open-Source Blue Team Tools – 2025

10 Best Open-Source Blue Team Tools – 2025

Companies evaluate their cybersecurity posture and protect network infrastructure implementations by employing cybersecurity experts to undertake security assessments.

The organization may engage penetration testers to conduct offensive attacks against the established security measures for the infrastructure.

The company will concurrently employ its cybersecurity professionals and Cybersecurity Analysts to proactively protect its network and test its personnel, policies, and procedures.

The offensive experts are designated as the “red team,” while the defensive professionals are defined as the “blue team.”

What Is A Blue Team?

A cybersecurity blue team maintains and protects an organization’s security from cyberattacks. They also develop strategies to increase a company’s security defenses by continuously monitoring its security posture.

As part of the blue team, you will automate secure systems, manage incidents, and acquire threat intelligence.

IT security experts utilize blue team tools to protect against simulated cyber threats launched by the “red team” to improve cybersecurity and penetration testing procedures.

In cybersecurity and penetration testing simulations, the phrases “red team” and “blue team” are used, with “red team” representing “attackers” and “blue team” representing “defenders.”

Blue team tools are software applications IT security experts employ to defend against a simulated cyberattack. Simulation of an attack and a defense is an excellent technique for enhancing cybersecurity and intrusion protection.

Skills Of A Blue Team

Although their technical focus is defense, the blue team actively participates in prevention. This team identifies and mitigates risks and threats before they damage the company.

Even the most skilled cybersecurity professionals struggle to keep up with the growing intelligence of cyberattacks and attackers. The blue team is in charge of observation, protection, and recovery. A member of the blue team should have the following abilities:

  • Risk assessment: A risk assessment enables identifying and allocating protective resources for at-risk valuable pieces.
  • Strengthening techniques: To enhance the organization’s security, a blue team must understand how to address vulnerabilities.
  • Threat defense necessitates knowledge: Blue teams must anticipate an attacker’s approach.
  • Detection and monitoring systems: As a member of the blue team, I must be familiar with packet sniffer devices, SIEM systems, IDS, and IPS.
  • Technical hardening skills: Professional hardening skills must be entirely prepared for any attacker or intrusion, and all systems must be hardened to decrease the exploit’s attack surface. Hardening includes blocking DNS attacks and reducing their attack surface, among other measures.
  • Familiarity with SIEM: Security information and event management (SIEM) is a subset of information security that combines security information management (SIM) with security event management (SEM) in software products and services (SEM). A red team examines security alarms produced by network and application hardware in real-time.

What Does A Blue Team Do?

Blue teams establish security precautions around an organization’s most valuable assets. Therefore, after collecting data and recording what must be defended, the blue team performs a risk assessment by discovering risks and vulnerabilities that these vulnerabilities can exploit.

Teams in blue conduct risk evaluations. They evaluate fundamental capacities, determine how their elimination will affect the organization, and document the significance of these resources.

Then, professionals are instructed on security measures, and more stringent password regulations are created to restrict system access. Typically, a monitoring tool is implemented to log and analyze system access.

Blue teams will perform DNS audits, scan internal and external systems for weaknesses, and collect network traffic samples as part of routine maintenance. Here are some tasks that a blue team does.

  • Monitoring domain name servers (DNS) for phishing attacks, stale DNS vulnerabilities, DNS record deletion unavailability, and decreasing DNS and online attacks.
  • We use digital footprint analysis to follow users’ actions and detect known security vulnerabilities.
  • Computers, iPads, and smartphones can be kept safe by installing endpoint security software, keeping antivirus software up to date, and correctly setting up the firewall access controls.
  • SIEM systems are used to log and ingest network traffic.
  • They identify an attacker’s activities by examining logs and memory, recognize and pinpoint an attack using these logs, and configure networks correctly by separating them.

Here Are Our Picks For The 10 Best Blue Team Tools:

  1. WazuhSIEM & XDR: Wazuh is an open-source SIEM and XDR platform for threat detection and response.
  2. Wireshark: Network protocol analyzer for capturing and analyzing network traffic to detect and troubleshoot network issues.
  3. ClamAV: Open-source antivirus engine for detecting malware and viruses on various operating systems and email servers.
  4. Snort: Network intrusion detection and prevention system for real-time traffic analysis and packet logging.
  5. Nikto: Web server scanner for identifying vulnerabilities and security issues in web applications and servers.
  6. OpenVAS: Comprehensive vulnerability scanner for identifying network, application, and device security issues.
  7. Yara: Tool for malware research and detection through pattern matching and rules-based analysis.
  8. Sigma | SIEM Signatures: Generic signature format for describing log events to be converted to SIEM queries.
  9. Nmap: Network discovery and security auditing tool for scanning and mapping networks to identify devices and services.
  10. OSQuery: SQL-based tool for querying and monitoring operating system data, processes, and configurations.
10 Best Blue Team Tools Features Stand Alone Feature Free Trial / Demo
1. WazuhSIEM & XDR Monitors logs and systems for anomalies.
Tracks and analyzes endpoint behavior.
Detects unauthorized file changes instantly.
Supports PCI-DSS, HIPAA, GDPR compliance.
Wazuh is an open-source SIEM and XDR platform for threat detection, monitoring, and response. No
2. Wireshark Network protocol analysis.
Real-time packet capture.
Detailed traffic inspection.
Extensive protocol support.
Open-source and highly reliable.
Network protocol analyzer for deep packet inspection. No
3. ClamAV Open-source antivirus software.
Real-time malware detection.
Email scanning capabilities.
Command-line interface.
Regular virus database updates.
Open-source antivirus engine for detecting malicious software. No
4. Snort Real-time intrusion detection.
Network traffic analysis.
Signature-based threat detection.
Open-source and customizable.
Extensive community support.
Network intrusion detection and prevention system (IDS/IPS). No
5. Nikto Web server vulnerability scanner.
Comprehensive security checks.
Fast and easy to use.
Open-source tool.
Regularly updated signatures.
Web server scanner for identifying vulnerabilities and misconfigurations. No
6. OpenVAS Comprehensive vulnerability scanning.
Detailed security assessments.
Open-source and modular.
Regular updates and support.
Wide range of testing options.
Comprehensive open-source vulnerability assessment and management solution. No
7. Yara Pattern-matching tool for malware.
Custom rule creation.
Lightweight and efficient.
Open-source and flexible.
Widely used in malware research.
Pattern matching tool for malware identification and classification. No
8. Sigma | SIEM Signatures Unified SIEM signature format.
Cross-platform compatibility.
Easy rule creation.
Open-source community-driven.
Supports various SIEM systems.
Generic signatures for consistent SIEM log analysis No
9. Nmap Network discovery and security auditing.
Host and service detection.
Port scanning capabilities.
Open-source and widely used.
Extensive scripting support.
Network discovery and security auditing tool. No
10. OSQuery Operating system analytics tool.
SQL-based query interface.
Real-time system monitoring.
Cross-platform compatibility.
Open-source and extensible.
SQL-powered tool for querying operating system data. No

1. WazuhSIEM & XDR

Wazuh is a free, open-source security platform used for threat detection, incident response, and compliance. It functions as both a SIEM (Security Information and Event Management) and XDR (Extended Detection and Response) solution.

Wazuh collects and analyzes security data from endpoints, networks, and cloud environments. It supports log analysis, file integrity monitoring, vulnerability detection, and intrusion detection.

Agents are deployed on endpoints to gather data and send it to a centralized manager. The platform features a powerful rules engine for detecting anomalies and threats.

It integrates with third-party tools like Elasticsearch and Kibana for data visualization and querying. Wazuh is ideal for blue teams seeking a scalable, cost-effective, and customizable security solution.

Why Do We Recommend It?

  • Free and open-source, making it cost-effective with no licensing fees.
  • Provides robust SIEM and XDR capabilities for threat detection, monitoring, and response.
  • Offers real-time security visibility across endpoints, networks, and cloud environments.
  • Highly customizable with flexible agent-based architecture and wide OS support.
  • Integrates easily with other security tools and supports compliance frameworks (e.g., PCI DSS, HIPAA).
  • Backed by an active community and frequent updates, ensuring continuous improvement and support.

Pros 

  • Free and open-source with active community
  • Real-time threat detection and response
  • Integrates easily with diverse IT systems
  • Centralized monitoring for better incident management

Cons 

  • Steep learning curve for new users
  • Complex configuration for advanced setups
  • Limited out-of-the-box threat intelligence
  • Requires significant system resource allocation

2. Wireshark

Blue Team Tools

Wireshark is the premier network traffic scanner in the world and an indispensable tool for blue team experts or systems administrators.

This blue team tool software allows you to study network traffic in real time and is frequently the finest tool for diagnosing network problems.

It is a network scanner or an application that captures packets from a wired connection, such as the link between the computer and the home office or the internet.

In an Ethernet network, a discrete data unit is called a packet. The most popular packet sniffer in the world is Wireshark. Wireshark, like any other packet sniffer, performs three functions:

  • Paket capture: Wireshark monitors a data connection in real time and captures total traffic flows, which may contain hundreds of thousands of packets.
  • Filtering: Using filters, Wireshark can slice and dice every bit of this random live data. Using a filter, you can retrieve only the information you require.
  • Visualization: Like any excellent packet sniffer, Wireshark enables users to explore the center of network transmission.
  • Additionally, it permits the visualization of full discussions and network flows.

Why Do We Recommend It?

  • Wireshark detects and translates binary traffic into a format that humans can read.
  • Wireshark supports over 2,000 network protocols, many obscure, unusual, or antiquated; the current security professional will find IP packet analysis the most valuable.

Pros 

  • It can monitor network traffic in real time.
  • Enables network activity monitoring at the microscopic level. 
  • It can provide results that are useful for analysis.
  • It is also capable of analyzing dropped packets.
  • Supports the network analyst in detecting security vulnerabilities and resolving latency problems.
  • It works with different operating systems.

Cons 

  • Since it sees everything on a tiny scale, it can be challenging for new users to understand.
  • UI could look better and be easier to use.
  • Since there is too much network information, finding what you are looking for takes time.

3. ClamAV

ClamAV is a free email, web, and endpoint protection antivirus application. It includes, among other things, a flexible and scalable multi-threading daemon, a command-line scanner, and a sophisticated tool for automating database modifications.

ClamAV is merely a command-line software; however, it may be controlled using a graphical interface called ClamAV. It is also compatible with desktop operating systems like Windows and macOS. It can scan multiple file types for vulnerabilities.

Supported formats include RAR, Zip, Gzip, Tar, Cabinet, OLE2, CHM, SIS format, BinHex, and virtually every email system.

Why Do We Recommend It?

  • It is a command-line scanner.
  • It is equipped with a Milter interface for Sendmail
  • In this powerful database installer, scripted changes and digital signatures are supported.
  • Natively supported document formats include MS Office and Mac Office files, HTML, Flash, RTF, and PDF.
  • ELF executables and Portable Executable files packed using UPX, FSG, Petite, NsPack, wwpack32, MEW, Upack, and obfuscated using SUE, Y0da Cryptor, and others have built-in support.

Pros 

  • ClamAV is an excellent software that detects and removes trojans, malware, and viruses from your system.
  • ClamAV is a C++-based, open-source antivirus that can recognize viruses, trojans, and other forms of malware.

Cons 

  • ClamAV is not the best antivirus software available, but using a Linux-only desktop will suffice. However, it may also encounter a higher rate of false positives than other leading antivirus software.
  • ClamAV also scored poorly in an AV-Test, an independent IT-security organization, Linux antivirus evaluation.

4. Snort

Snort is a network-based intrusion detection system written in the C programming language. It is open-source software that is available for free.

It can also be employed as a real-time packet sniffer to examine the system. The network administrator can use it to monitor all packet data and identify potentially harmful ones.

It is based on the packet capture utility from the library. The rules are simple to write and apply and may be used in any operating system and network context.

The key reason for this IDS’s popularity over others is that it is free-to-use software that is also open source, allowing any user to use it. 

Why Do We Recommend It?

  • Real-time traffic monitor
  • Packet logging
  • Analysis of protocol
  • Content matching
  • OS fingerprinting
  • Compatible with all network environments.
  • Creates logs
  • Open Source
  • Rules are easy to implement

Pros 

  • It is quick and easy to install on networks.
  • Rules are easy to write.
  • It has good support available on Snort sites and its listserv.
  • It is free for administrators who need a cost-effective IDS.

Cons 

  • The administrator must come up with ways to log and report.
  • The token ring is not supported in Snort.
  • Despite its adaptability, commercial intrusion detection systems have features that Snort does not have.

5. Nikto

Blue Team Tools

Nikto is a web application scanner that proclaims itself loudly and proudly. It’s free and includes valuable tools like a web server scanner, a database of known malicious files, and a configuration verification tool.

Nikto isn’t undetectable and doesn’t try to be, but it still works. This free blue team tool can scan web servers thoroughly and detect threats from a database of nearly 7,000 malicious files and data.

Why Do We Recommend It?

  • Identifies 1250 servers running out-of-date software
  • Fully compatible with the HTTP protocol
  • Templates can be used to make custom reports.
  • Several server ports scan simultaneously.

Pro 

  • Freely available for users 
  • Available in Kali Linux 

Con 

  • It does not have a community platform. 
  • It does not have a GUI

6. OpenVAS

Greenbone Networks maintains and distributes the Open Vulnerability Assessment System (OpenVAS), a vulnerability scanner.

It is designed to be an all-in-one vulnerability scanner, with various built-in tests and a Web interface that makes setting up and conducting vulnerability scans quick and easy while offering a high level of user customization.

To scan for security vulnerabilities, employ OpenVAS, which is compatible with Linux. It comes with its virtual machine or can be set up from the ground up using the code available under the GNU’s General Public License (GPL).

Why Do We Recommend It?

  • An Advanced Task Wizard is also included in the OpenVAS web interface.
  • It includes several default scan configurations and allows users to create custom configurations.

Pros

  • It is free and open source and can perform more advanced functions than other tools, such as Nessus.

Cons 

  • It isn’t easy to install, configure, and use 

7. Yara

Blue Team Tools

YARA is a tool designed to assist malware researchers in identifying and classifying malicious files. YARA can generate summaries of malware families using textual or binary patterns found in samples of such families.

Each description comprises a string and a Boolean expression that specifies its logic.

Why Do We Recommend It?

  • Using binary strings with wildcards, complex and robust rules can be defined.
  • Case-sensitive string comparison
  • It has special operators
  • It has regular expressions

Pros 

  • Find files that match rules and patterns written in a special-purpose language.

Cons 

  • Behavior analysis is a more effective way of detecting malware than YARA’s pattern/string/signature matching. YARA detection can be readily circumvented as a result.

8. Sigma | SIEM Signatures

Sigma is a blue team tool for creating and using signatures with security information and event management (SEIM) systems.

It is designed to help security professionals known as blue teams identify and respond to potential security threats by providing a standardized format for writing and sharing signatures.

These signatures can detect known vulnerabilities and malicious activity, such as malware infections or network intrusions, and can help the blue team respond quickly to potential security incidents. 

Why Do We Recommend It?

  • A standardized format of writing and sharing signatures, making it easy for security professionals to create and use them across different SIEM systems.
  • Support multiple log sources, including Windows event logs, Syslog, and JSON logs.
  • The ability to detect known malicious activity, such as malware infections or network intrusions.

Pros

  • It is an open-source blue team tool, making it freely available.
  • It is easy to use, even for those without advanced technical knowledge. 
  • It can be used with multiple log sources, making it versatile and practical in various environments. 

Cons 

  • It relies on predefined signatures and may be unable to detect unknown or zero-day threats.
  • It may generate many false positives, which can be challenging to sort through and require additional investigation resources.
  • Working effectively with different SIEM systems may require additional configurations and customizations.

9. Nmap

NMAP is an acronym for Network Mapping. It aids in network mapping by inspecting ports, exploring operating systems, and establishing an inventory of services and equipment.

This suite is excellent for network penetration testing. NMAP sends packets with different structures for each transport layer protocol. The packets come back with IP addresses and other data.

You can use this information to find servers, learn about OS fingerprints and services, and check for security vulnerabilities. NMAP is a robust program that can map a massive network with thousands of accessible ports.

Using NMAP, network administrators can compile a list of all the hardware, software, and services currently connected to a network, thus identifying potential security vulnerabilities.

Pros 

  • Open-source software is, therefore, readily accessible and easily verifiable.
  • Easy to navigate 
  • Lots of networking features 

Cons 

  • Utilization requires extensive knowledge.
  • Limited scanning depth
  • Utilized by both malicious hackers and security professionals

10. OSQuery

Blue Team Tools

OSquery is a blue team tool for performing real-time endpoint visibility and system auditing on Windows, macOS, and Linux systems.

It is designed to help security professionals identify and respond to potential security threats by providing detailed information about the state of their systems.

OSQuery uses an SQL-based query language to access information about the operating system, such as running processes, installed software, network connections, and file system changes.

This information can be used to detect suspicious activity and identify potential security incidents. 

Why Do We Recommend It?

  • Real-time endpoint visibility and system auditing.
  • SQL-based query language is used to access information about the operating system.
  • Support Windows, macOS, and Linux systems.
  • An extensive library of predefined tables and queries makes it easy to find the needed information.

Pros 

  • It is an open-source tool.
  • It is easy to use
  • It can be used by multiple operating systems, making it versatile and practical in various environments.

Cons 

  • It may require additional configurations and customizations to work effectively in different environments.
  • It may require additional setup and maintenance to keep it running smoothly.
  • It may generate a large amount of data, requiring additional resources to process and analyze.

Conclusion 

Cyber Security experts know cybersecurity is an ever-evolving profession; attackers will always discover a way to circumvent vulnerabilities in web applications.

Multinational enterprises like Yahoo, Equifax, and Sony have fallen victim to these evil people. The Red Team operation can uncover these vulnerabilities before real criminals use them.

This exercise boosts Blue Team’s efficacy because it allows firms to increase their security and assess the unintentional repercussions of any cyber incident. The cybersecurity profession must learn more about combining these two teams and learning from each other.

FAQs

  1. What is the blue team strategy?

As the entity’s first line of defense, the blue team uses security tools, protocols, systems, and other resources to protect the organization and find weaknesses in its ability to recognize threats.

The environment for the blue team should be the same as the organization’s existing security system, which may have techniques that aren’t set up right, software that hasn’t been updated, or other known or unidentified threats.

Here are some examples of blue team assessments:

  • Performing DNS research
  • Performing digital analysis to establish a baseline of network connections and more readily identify odd or suspicious behavior
  • Assessing, deploying, and monitoring all environment-wide security software
  • Ensure that perimeter security technology, such as firewalls, antiviral, and anti-malware software, is correctly configured and current.
  • Implementing least-privilege access means the organization allows the lowest access available to each user or device. This can help prevent lateral network movement in the case of a breach.
  • Utilizing micro-segmentation, a security strategy splits perimeters into small zones to retain distinct network access to every component.
  1. What is a blue team analysis?

A blue team analysis refers to the process of evaluating and analyzing an organization’s security posture to identify potential vulnerabilities, risks, and areas for improvement.

A blue team analysis aims to proactively identify and mitigate security threats before attackers can exploit them. Here are the steps included in the blue team analysis.

  • Asset discovery 
  • Vulnerability scanning 
  • Penetration testing 
  • Risk assessment 
  • Compliance checking 
  • Security Checking 

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Chad Barr

Chad Barr is a visionary and executive leader, blending over two decades of expertise with a unique ability to demystify complex technical concepts. As a cybersecurity leader, prolific author, and director at AccessIT Group, Chad has empowered organizations across diverse industries to build resilient security frameworks. His engaging writing, speaking engagements, and thought leadership inspire proactive cybersecurity practices, making him a trusted voice in the ever-evolving digital landscape.

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