Incomplete cache verification issue in GitHub Enterprise Server leading to exposure of private repo files

Summary

An improper cache key vulnerability was identified in GitHub Enterprise Server that allowed an unauthorized actor to access private repository files through a public repository. To exploit this, an actor would need to already be authorized on the GitHub Enterprise Server instance, be able to create a public repository, and have a site administrator visit a specially crafted URL. This vulnerability affected all versions of GitHub Enterprise Server prior to 3.6 and was fixed in versions 3.2.20, 3.3.15, 3.4.10, 3.5.7, 3.6.3. This vulnerability was reported via the GitHub Bug Bounty program.