git-filter-repo

Detecting and Removing Secrets from Git History with Betterleaks and git-filter-repo

Developers often accidentally commit sensitive data such as API keys, passwords, database dumps, or private uploads to Git repositories. Even after removal in a later commit, these secrets remain accessible in the commit history and can be recovered by anyone with repository access. The recommended approach begins with scanning the entire history using specialized tools to identify leaked credentials across all branches and past commits. Once identified, the secrets must first be rotated or revoked before any history rewriting occurs. Tools like Betterleaks provide detection with keyword filtering, entropy analysis, and Base64 decoding, while git-filter-repo enables precise removal of files and replacement of secret strings throughout the repository timeline. The process requires careful backups, coordination with teams, and force-pushing rewritten history, followed by fresh clones for all contributors and CI/CD systems. Even after cleanup, organizations must assume that old secrets may persist in forks, backups, or caches and therefore treat rotation as mandatory.