Yahoo Mail has been playing catch-up on security for the past few years, but at this year's Black Hat, the company announced plans for a feature most services are still struggling with: end-to-end encryption. The company has announced a new PGP plugin that it plans to debut in the fall. The software builds off of Google's PGP plugin, which is still in development, but Yahoo's new security team has forked off of the project to develop a number of new features, including mobile support. According to Forbes, newly hired security engineer Yan Zhu was instrumental in the project.