A path traversal vulnerability was identified in GitHub Pages builds on GitHub Enterprise Server that could allow an attacker to read system files. To exploit this vulnerability, an attacker would need permission to create and build a GitHub Pages site on the GitHub Enterprise Server instance. This vulnerability affected all versions of GitHub Enterprise Server prior to 3.3 and was fixed in versions 3.0.19, 3.1.11, and 3.2.3. This vulnerability was reported via the GitHub Bug Bounty program.
The product uses external input to construct a pathname that should be within a restricted directory, but it does not properly neutralize sequences such as ".." that can resolve to a location that is outside of that directory.
The product uses external input to construct a pathname that is intended to identify a file or directory that is located underneath a restricted parent directory, but the product does not properly neutralize special elements within the pathname that can cause the pathname to resolve to a location that is outside of the restricted directory.