Path traversal vulnerability in GitHub Enterprise Server that allowed arbitrary file read with a specially crafted GitHub Pages artifact upload

A path traversal vulnerability was identified in GitHub Enterprise Server that allowed an attacker to gain unauthorized read permission to files by deploying arbitrary symbolic links to a GitHub Pages site with a specially crafted artifact tarball. 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 3.12 and was fixed in versions 3.8.15, 3.9.10, 3.10.7, 3.11.5. This vulnerability was reported via the GitHub Bug Bounty program.