Open Source Security Solutions

Businesses now face a wide range of security threats, and cyberattacks are becoming more sophisticated by the day. To defend against these threats, businesses need an arsenal of security solutions; but securing networks and blocking threats can come at a cost. Fortunately, there are many open source security solutions that can greatly improve a business’s security posture at a very low cost. Many open source security solutions are available free of charge.  Some of the best open source security solutions have been listed below under their respective categories.

Open Source Firewalls

A firewall monitors and filters incoming and outbound network traffic based on the organization’s security policies and acts as a barrier between the public Internet and the internal network. Internal firewalls can also be implemented to prevent attackers from accessing applications and data if they breach the perimeter defenses.

Firewalls can be expensive, but there are several free and low-cost open source security solutions that have features and capabilities comparable to some of the most expensive commercial firewalls, with pfSense one of the most trusted and widely used open source firewalls. pfSense is based on the FreeBSD system and is suitable for use in home networks and large enterprises and has features such as routing, load balancing, site-to-site VPNs, IDS/IPS, and more.

OPNSense is another free open source firewall with a host of features for advanced users including flow monitoring, WAN load balancing, full mesh VPN routing, and an HTTP load balancer, with built-in reporting and analysis. OPNSense a highly active community that constantly reviews and improves the source code, and the firewall is regularly updated.

Open Source Security Information and Event Management (SIEM) Solutions

One of the most difficult and time-consuming tasks in IT security is checking security log files and monitoring for potential attacks in progress. Since an organization may use many security solutions – each generating its own logs and alerts – it can be difficult to analyze, prioritize, and act on critical information promptly. A SIEM solution makes it easier to manage security by filtering and collating data, adding context to alerts, prioritizing security issues, and even automating incident response.

There are several accomplished open source SIEM solutions available, such as Splunk Free and AlienVault OSSIM, with the latter being one of the most widely-adopted open source SIEM solutions. OSSIM is a unified platform that helps with asset discovery, vulnerability assessments, intrusion detection, and behavioral monitoring. While both of these solutions are excellent SIEM solutions, there are restrictions on use, which means you may need to pay for the premium versions of these open source security solutions to get the functionality you need.

Open Source Intrusion Detection Systems

Many SIEM solutions have intrusion detection capabilities such as the ability to detect lateral movement by correlating data from different IT systems. SIEM solutions allow IT professionals to take steps to prevent attacks, whereas an Intrusion Detection System (IDS) only detects and reports on events that could indicate an attack in progress. Many companies use an IDS with a SIEM and feed data from the IDS into their SIEM, which provides a single user interface to read data from all security solutions.

There are excellent open source IDSs available with two of the most commonly used being Snort and OSSEC+. Other open source security solutions include Bro, for detecting suspicious signatures and anomalies, Kismet for identifying unauthorized wireless access points, and Open DLP – a data loss prevention tool that can identify unauthorized copying and transmission of data.

Open Source Vulnerability Assessment Tools

Vulnerability scanning is an important security best practice to adopt to ensure loopholes, misconfigurations, and other vulnerabilities are identified and mitigated before they can be found and exploited by hackers. These open source security solutions help to ensure the confidentiality, integrity, and availability of systems and data. There are many vulnerability scanning tools that IT security professionals can use, and if you have a tight budget, many powerful open source vulnerability tools are available for little or no cost.

OpenVAS is one of the most popular open source vulnerability assessment tools and also one of the most advanced scanners and vulnerability managers available. OpenVas is a comprehensive vulnerability assessment system that can detect a wide range of security issues in servers and network devices, and performs more than 53,000 network vulnerability tests (NVTs).

Nmap is a free-to-use, flexible open source network scanning tool that can be used by IT security professionals for network discovery and security auditing. Nmap identifies hosts, services, operating systems, open ports, and security risks by sending packets and analyzing the responses. The tool can be used to monitor single hosts or huge networks containing hundreds of thousands of devices.

Burp Suite (Free) is a web application vulnerability scanner that can be used to test web applications for vulnerabilities, and inspect and modify traffic between the browser and application. The paid versions of the solution automate scans, although the community version allows scans to be performed manually for free.

Nikto is a web server scanner that performs scans for a range of different vulnerabilities such as outdated software, configuration issues, and unsafe files and programs. The tool will identify installed web servers and software, although suggestions are not provided for mitigating the vulnerabilities.

Powerfuzzer is a customizable and automated HTTP-based web fuzzer that can be used to identify vulnerabilities in websites such as cross-site scripting, SQL injection, HTTP 500 statuses, and CRLF.

Open Source Security Solutions for Password Management

A lot of attention is focused on vulnerabilities in software, but one of the most common vulnerabilities to be exploited by cyber threat actors is weak passwords. Credential stuffing attacks and other brute force tactics are often used to guess weak passwords. While password policies can be implemented to force employees to use strong passwords, employees often set passwords that comply with an organization’s password policies but are still very susceptible to brute force attacks. There are open source security solutions available that can help prevent these password vulnerabilities.

A password manager allows users to generate complex, unique passwords for all accounts and stores them securely in an encrypted password vault. All users need to remember is one master password or passphrase for their password vault.

There are several open source password managers available, such as Bitwarden and KeePass. Bitwarden offers an impressive free tier, although the premium version is very competitively priced. The solution is easy to use, makes sharing passwords simple, and it is easy to implement access control policies for groups and individuals. Importantly, there is a highly active Bitwarden community, and the source code – released under GPLv3 license – has undergone an independent review. There is also a bug bounty program on HackerOne that encourages open source community members to look for – and report – vulnerabilities in the code.

KeePass is a free open source password manager primarily for Windows, although versions have now been released for Mac OS X and Linux. KeePass has highly secure encryption algorithms (AES/Twofish), although it is not as user-friendly and lacks some of the features present in other password managers. The KeePass source code was released under a GPLv2 license and was reviewed in 2016 under the FOSSA pilot project, which found no major security issues.