claude-code-action/docs/security.md

Security

Access Control

• Repository Access: The action can only be triggered by users with write access to the repository
• Bot User Control: By default, GitHub Apps and bots cannot trigger this action for security reasons. Use the allowed_bots parameter to enable specific bots or all bots
• ⚠️ Non-Write User Access (RISKY): The allowed_non_write_users parameter allows bypassing the write permission requirement. This is a significant security risk and should only be used for workflows with extremely limited permissions (e.g., issue labeling workflows that only have issues: write permission). This feature:
  • Only works when github_token is provided as input (not with GitHub App authentication)
  • Accepts either a comma-separated list of specific usernames or * to allow all users
  • Should be used with extreme caution as it bypasses the primary security mechanism of this action
  • Is designed for automation workflows where user permissions are already restricted by the workflow's permission scope
• Token Permissions: The GitHub app receives only a short-lived token scoped specifically to the repository it's operating in
• No Cross-Repository Access: Each action invocation is limited to the repository where it was triggered
• Limited Scope: The token cannot access other repositories or perform actions beyond the configured permissions

GitHub App Permissions

The Claude Code GitHub app requires these permissions:

• Pull Requests: Read and write to create PRs and push changes
• Issues: Read and write to respond to issues
• Contents: Read and write to modify repository files

Commit Signing

All commits made by Claude through this action are automatically signed with commit signatures. This ensures the authenticity and integrity of commits, providing a verifiable trail of changes made by the action.

⚠️ Authentication Protection

CRITICAL: Never hardcode your Anthropic API key or OAuth token in workflow files!

Your authentication credentials must always be stored in GitHub secrets to prevent unauthorized access:

# CORRECT ✅
anthropic_api_key: ${{ secrets.ANTHROPIC_API_KEY }}
# OR
claude_code_oauth_token: ${{ secrets.CLAUDE_CODE_OAUTH_TOKEN }}

# NEVER DO THIS ❌
anthropic_api_key: "sk-ant-api03-..." # Exposed and vulnerable!
claude_code_oauth_token: "oauth_token_..." # Exposed and vulnerable!