title: Improper access control in GitHub Enterprise Server leading to the disclosure of Actions secrets to forks
description: An improper access control vulnerability was identified in GitHub Enterprise Server that allowed an authenticated user with the ability to fork a repository to disclose Actions secrets for the parent repository of the fork. This vulnerability existed due to a flaw that allowed the base reference of a pull request to be updated to point to an arbitrary SHA or another pull request outside of the fork repository. By establishing this incorrect reference in a PR, the restrictions that limit the Actions secrets sent a workflow from forks could be bypassed. This vulnerability affected GitHub Enterprise Server version 3.0.0, 3.0.0.rc2, and 3.0.0.rc1. This vulnerability was reported via the GitHub Bug Bounty program.
problem types: CWE-285: Improper Authorization
affected:
{
product: GitHub Enterprise Server
vendor: GitHub
versions:
lessThan: 3.0.1, status: affected, version: 3.0, versionType: custom
}