Open G Hub writes directly to mouse hardware registers via HID++ 2.0 over USB HID. The primary risks are:

1. Device bricking — sending invalid commands could render the mouse unresponsive
2. Unauthorized device modification — malicious code could alter mouse behavior
3. Privilege escalation — the tool requires HID device access (udev rules or WinUSB driver)

Only known-safe HID++ feature IDs are allowed. Any request targeting an unlisted feature is rejected before reaching the device. The whitelist is defined in crates/core/src/safety.rs:

Explicitly blocked (not in whitelist):

• Firmware update / DFU features
• Raw memory read/write
• Manufacturing/debug features
• Any undocumented feature IDs

All write parameters are validated against hardware-safe ranges before any HID communication:

• DPI: 100-25,600 (step 50)
• Polling rate: 125, 250, 500, or 1000 Hz only
• Button index: 0-5 only
• Button actions: CID-to-CID remapping only (no macro injection)

• No firmware operations: Firmware read/write/update is completely out of scope
• No macro support: Onboard macro programming requires profile memory writes with higher bricking risk
• No raw register access: All communication goes through the typed feature API
• No network access: The application has no network capability
• No telemetry: Zero data collection or phone-home

The G502 Lightspeed does not expose a firmware checksum validation feature via HID++ 2.0. The DEVICE_FW_VERSION feature (0x0003) provides firmware version strings but no integrity verification. This is a hardware limitation, not a software decision.

Enable structured trace logging to capture all HID++ transactions for post-hoc review:

RUST_LOG=trace open-g-hub-cli set-dpi 1600 2> audit.log

This logs:

• Every HID++ request (TX) with feature index, function ID, and parameter bytes
• Every HID++ response (RX) with full payload
• All safety validation checks (pass/fail)
• Error classification and retry decisions

For persistent audit logging, configure tracing-subscriber with a file appender (not yet built-in; can be added via tracing-appender crate).

If you discover a security issue (e.g., a way to bypass the safety layer, send unauthorized HID++ commands, or cause device damage), please:

1. Do not open a public issue
2. Email the maintainers directly (see repository contact info)
3. Include steps to reproduce and the HID++ commands involved
4. We will respond within 72 hours

If a mouse becomes unresponsive:

1. Unplug the USB cable / remove the receiver
2. Wait 10 seconds
3. Replug — most HID++ devices have hardware-level reset on power cycle
4. Factory reset: hold DPI button + left click while plugging in (model-specific, consult Logitech)
5. Contact Logitech support for hardware-level recovery