A pull request branch is a Git branch proposed for review and merge into another branch, usually the main codebase. Teams use it to test new features, bug fixes, and configuration changes before they become part of production code.
In cyber security, pull request branches matter because they sit at the boundary between untrusted changes and trusted software. Attackers who can alter a branch, its metadata, or the checks around it may be able to inject malicious code, bypass review, or influence CI/CD jobs. Defenders protect these branches with strict permissions, branch protection rules, required reviews, and limited token scopes so that only approved changes can reach the main branch.