Skip to content
GitLab
Next
    • GitLab: the DevOps platform
    • Explore GitLab
    • Install GitLab
    • How GitLab compares
    • Get started
    • GitLab docs
    • GitLab Learn
  • Pricing
  • Talk to an expert
  • /
  • Help
    • Help
    • Support
    • Community forum
    • Submit feedback
    • Contribute to GitLab
    Projects Groups Topics Snippets
  • Register
  • Sign in
  • GitLab GitLab
  • Project information
    • Project information
    • Activity
    • Labels
    • Members
  • Repository
    • Repository
    • Files
    • Commits
    • Branches
    • Tags
    • Contributor statistics
    • Graph
    • Compare revisions
    • Locked files
  • Issues 54.9k
    • Issues 54.9k
    • List
    • Boards
    • Service Desk
    • Milestones
    • Iterations
    • Requirements
  • Merge requests 1.5k
    • Merge requests 1.5k
  • CI/CD
    • CI/CD
    • Pipelines
    • Jobs
    • Artifacts
    • Schedules
    • Test cases
  • Deployments
    • Deployments
    • Environments
    • Releases
  • Packages and registries
    • Packages and registries
    • Package Registry
    • Container Registry
    • Terraform modules
    • Model experiments
  • Monitor
    • Monitor
    • Incidents
  • Analytics
    • Analytics
    • Value stream
    • CI/CD
    • Code review
    • Insights
    • Issue
    • Repository
  • Snippets
    • Snippets
  • Activity
  • Graph
  • Create a new issue
  • Jobs
  • Commits
  • Issue Boards
Collapse sidebar
  • GitLab.orgGitLab.org
  • GitLabGitLab
  • Issues
  • #29683
Closed
Open
Issue created Jun 25, 2019 by GitLab SecurityBot@gitlab-securitybotReporter

Endpoint for auto-completing Assignee discloses the members of private groups

HackerOne report #627507 by ngalog on 2019-06-24, assigned to estrike:

Summary

I have a project, with id 10257668, and I have invited a private group as a developer to this project. As that group is private, you should not see its membership. However, there is a way to find out project's private membership:

  • Correct permission check: https://gitlab.com/api/v4/projects/:project_id/members - does not disclose private group's membership.
  • Incorrect permission check: https://gitlab.com/autocomplete/users.json?search=&active=true&project_id=10257668&current_user=true - discloses the members of private group.

Steps to reproduce:

  1. Login to gitlab.com.
  2. Visit this project members page: https://gitlab.com/api/v4/projects/10257668/members. See this project has only one member.
  3. Visit https://gitlab.com/autocomplete/users.json?search=&active=true&project_id=10257668&current_user=true. See this project has more than one member, thus disclosing the private membership.

Impact

Disclosure of members in a private group.

Proposal

The autocomplete endpoint should use the permission check from the Project Members API endpoint (https://gitlab.com/api/v4/projects/[project-id]/members).

Edited Aug 24, 2021 by Dan Jensen
Assignee
Assign to
Time tracking