Report a vulnerability privately through the repository's GitHub Security tab. Include the affected version, command, platform, synthetic reproduction, and the impact on artifact integrity, signer verification, recipient confidentiality, or safe extraction. Never include real private keys, plaintext submissions, decrypted feedback, tokens, or event secrets.

• eventctl is offline. It does not authenticate GitHub users, call GitHub, mutate a registry, enforce organizer policy, or run submitted code.
• GitHub Actions binds a request manifest's numeric github_id to the account that opened its pull request. The protected controller verifies this before accepting an artifact.
• Team membership, names, and registered public keys become immutable when a team is activated. Operational status and scoring remain trusted registry state.
• Ed25519 signing and age hybrid ML-KEM768/X25519 encryption use independent key pairs. Do not reuse, commit, or share either private key.
• Treat every decrypted feedback file and submitted artifact as untrusted data. Only an event-specific isolated scorer may execute it.
• decverify extracts only flat files/<name> entries into an initially empty directory. Do not bypass that boundary by manually unpacking untrusted tars.
• A public Actions artifact is not a confidentiality boundary. Upload only feedback encrypted to the team's registered encryption public keys, never raw scorer logs.

Only the current eventctl/v3 protocol is supported. Event repositories should pin the exact released CLI and review protocol changes before upgrading.