Preen invokes existing Linux tools and some operations can delete files, remove packages, change services or alter system configuration. Keep backups, review the target and use a disposable test system when possible. Run Preen as your normal user; supported privileged operations request authorization via polkit. Never share a password, access token or private configuration in a report.

Turn on Simulate to preview supported maintenance actions and inspect Logs before making a real change. Simulate is not a complete no-write sandbox: read-only checks still run, saving preferences or logs can write files, and legacy settings migration may occur. A simulated command is not a complete preview of package-manager dependency changes. Direct app-uninstall protection covers a defined set of essential APT package names; APT autoremove and indirect dependencies can affect other packages. Size estimates are not guarantees, and backup archives are not encrypted by Preen. These measures reduce risk; they do not replace review or a usable backup.

Please do not publish exploit details, credentials or private data in a public issue. GitHub private vulnerability reporting for this repository was disabled when this policy was updated on 2026-10-28. If the repository later shows a Report a vulnerability option on its Security tab, use that private channel.

Otherwise, check the maintainer's GitHub profile for an available private contact method. If none is listed, open a minimal public issue asking how to establish a private channel; include no exploit, secret or identifying data. Once a private channel is agreed, share the affected version or commit, environment, reproduction steps, potential impact and any relevant redacted logs. Do not test against systems or accounts without permission.

There is no published response-time guarantee or formal supported-version schedule. Older releases may not include fixes present on the default branch; consult the changelog and verify the exact release or commit you run. Maintainers can enable GitHub private vulnerability reporting to make future confidential reports easier.

Doctor reports, logs, screenshots and exported configuration archives can contain usernames, absolute paths, installed apps, tokens or other private data. Inspect and redact them before sharing, and send only what is necessary. See the privacy policy for storage and retention details.