An open source project is software whose source code is publicly available for anyone to inspect, use, modify, and contribute to. In cybersecurity, this visibility is valuable because defenders can audit code for vulnerabilities, verify how data is handled, and patch flaws without waiting for a vendor’s private review process. Open source is not automatically secure, though: attackers can read the same code, so security depends on active maintenance, review, and timely updates.
In real attacks, open source projects are often targeted through the supply chain rather than the code itself: malicious commits, compromised maintainers, dependency poisoning, or typosquatted packages can slip into trusted builds. Defenses include code review, signed releases, reproducible builds, dependency pinning, and community auditing. For security teams, open source is both an advantage and a responsibility: it makes verification possible, but only if the project has enough contributors to keep watch.