The code hosting service GitHub confirmed that the introduction of GitHub security alerts in November allowed to obtain a significant reduction of vulnerable code libraries on the platform.

Github alerts warn developers when including certain flawed software libraries in their projects and provide advice on how to address the issue.

Last year GitHub first introduced the Dependency Graph, a feature that lists all the libraries used by a project. The feature supports JavaScript and Ruby, and the company also plans to add the support for Python this year.

GitHub Security Alerts

The GitHub security alerts feature introduced in November is designed to alert developers when one of their project’s dependencies has known flaws. The Dependency graph and the security alerts feature have been automatically enabled for public repositories, but they are opt-in for private repositories.

The availability of a dependency graph allows notifying the owners of the projects when it detects a known security vulnerability in one of the dependencies and suggests known fixes from the GitHub community.

The new feature analyzes vulnerable Ruby gems and JavaScript NPM packages based on MITRE’s Common Vulnerabilities and Exposures (CVE) list, every time a new vulnerability is discovered is added to this list and all repositories that use the affected version are identified and their maintainers informed.

“Vulnerabilities that have CVE IDs (publicly disclosed vulnerabilities from the National Vulnerability Database) will be included in security alerts. However, not all vulnerabilities have CVE IDs—even many publicly disclosed vulnerabilities don’t have them.” states GitHub.

“This is the next step in using the world’s largest collection of open source data to help you keep code safer and do your best work. The dependency graph and security alerts currently support Javascript and Ruby—with Python support coming in 2018.”

Github Users can choose to receive the alerts via the user interface or via email.

An initial scan conducted by GitHub revealed more than 4 million vulnerabilities in more than 500,000 repositories. Github notified affected users by December 1, more than 450,000 of the vulnerabilities were addressed either by updating the affected library or removing it altogether.

According to GitHub, vulnerabilities are in a vast majority of cases addressed within a week by active developers.

“By December 1 and shortly after we launched, over 450,000 identified vulnerabilities were resolved by repository owners either removing the dependency or changing to a secure version.” GitHub said. “Additionally, 15 percent of alerts are dismissed within seven days—that means nearly half of all alerts are responded to within a week. Of the remaining alerts that are unaddressed or unresolved, the majority belong to repositories that have not had a contribution in the last 90 days.”