The 2021 State of Open Source Vulnerabilities

Open source is everywhere. It comprises around 90% of the components of modern applications, and is used by developers across a wide range of industries. Unfortunately, as open source usage has increased, so too have vulnerabilities within open source code.

In this report, we’ll take an in-depth look at today’s open source vulnerability landscape, including areas like:

Common vulnerabilities

The distribution of vulnerabilities across popular languages

Longitudinal trends in vulnerabilities over several years

The most prevalent CWEs in each language

Libraries with the most vulnerabilities

Best practices to keep your organization’s software free of vulnerabilities


Up to 90% of any piece of software is from open source, creating countless dependencies and areas of risk to manage. FOSSA is the most reliable automated policy engine for security management, license compliance, and code quality across the open source stack. With FOSSA, engineering, security, and legal teams all get

complete and continuous risk mitigation for the entire software supply chain, integrated into each of their existing workflows. FOSSA enables organizations like Uber, Zendesk, Twitter, Verizon, Fitbit, and UiPath to manage their open source at scale and drive continuous innovation.

Use Cases

Risk Mitigation

FOSSA users benchmark 47% fewer false-positives by finding dependencies they actually rely on earlier in the SDLC.

Continuous Compliance

Get 90% faster insight in your CI/CD workflows — an average of four weeks shorter compliance implementation time.

Due Diligence

Only FOSSA delivers the most complete open source audit for IPOs and M&As plus 5% annualized engineering savings in the first week alone.