Email hello@ayal.tech with [yzel security] in the subject. Do not open a public issue for a vulnerability. Expect a first response within 7 days.

Please include the connector, the yzel version (yzel --version), and a minimal reproduction. If the report concerns a third-party service (1C, Bitrix24, Ozon, …), say whether you have already notified that vendor.

Yzel holds credentials for business systems that contain real commercial and personal data. Treat any credential-handling bug as high severity.

• Credentials at rest. AES-256-GCM encrypted in a local SQLite database at ~/.yzel/store.db. The key comes from the YZEL_KEY environment variable, or is generated at ~/.yzel/vault.key on first run. Nothing is transmitted anywhere except to the configured service.
• No telemetry. Yzel makes no network call other than to the service you configured.
• ~/.yzel/vault.key is a plaintext key file. If an attacker has your home directory they have your credentials. Set YZEL_KEY from your own secret manager if that matters to you.
• 21 of the 68 MCP tools mutate remote state (see docs/LIVE-CHECKS.md). An agent with a yzel connector attached can create, update and delete records in your production systems. Scope the API keys you give it accordingly — most services support read-only tokens, and Wildberries and Ozon both have sandbox modes.

Only the latest released version receives fixes. Yzel is 0.x; there is no LTS.