How GitHub used secret scanning to reach inbox zero

Several years ago, GitHub Security launched an initiative to assess and improve our overall secrets hygiene. As part of that effort, we piloted the Secret Scanning capability that was under development at the time. That’s when we found more than 20,000 secrets spread across our 15,000+ repositories. The number was significantly higher than we anticipated, but it quickly became clear that success would depend on identifying which alerts represented real risk, assigning ownership, and remediating them safely. Nine months later, we reached zero open alerts. New secret scanning customers often ask us: “How do you manage this internally? How did you actually clean up your existing secrets?” Like many long-running software companies, GitHub’s approach to secrets management evolved over time. GitHub was founded in 2008, before today’s centralized vaults, automated secret scanning, and dedicated secrets-management platforms were common across the industry. As engineering practices matured and GitHub grew, we continued investing in stronger controls, better tooling, and systematic risk reduction for legacy patterns. This work reflects our ongoing commitment to improving security, reducing exposure, and ensuring our internal practices meet the same high standards we expect across the industry. This blog post shares what worked for us during this effort, and highlights strategies you can apply to better protect your own secrets. Cutting out the noise The first thing we discovered was that the alert count was a bit misleading—i.e., 20,000 alerts did not mean 20,000 equally risky problems. When we dug into the data, we discovered that just five repositories accounted for roughly 18,000 of those alerts, and every one of those secrets was inactive: test fixtures, deactivated credentials, and fake-but-valid-looking secrets used for testing. (We build secret scanning, so naturally we have repositories full of legitimate-looking secrets in tests.) That left over 2,000 alerts that nee