GitHub Enterprise Server Information Disclosure Vulnerability Exposes Private Repository Names via Search API

An exposure of sensitive information vulnerability was identified in GitHub Enterprise Server that could allow an attacker to disclose the names of private repositories within an organization. This issue could be exploited by leveraging a user-to-server token with no scopes via the Search API endpoint. Successful exploitation required an organization administrator to install a malicious GitHub App in the organization’s repositories. This vulnerability impacted only GitHub Enterprise Server version 3.17 and was addressed in version 3.17.2. The vulnerability was reported through the GitHub Bug Bounty program.