fix(core): correct BLE MAC address display
What the developer wrote
Authored by Roman Zeyde
fix(core): correct BLE MAC address display
[no changelog]
What changed, and why it matters
This commit fixes a display bug in the Trezor hardware wallet where the Bluetooth (BLE) MAC address was shown backwards on the device menu. The internal code stored the address bytes in reverse order, but the screen formatter was not flipping them back before showing them to the user. This is a user-interface correctness fix, not a cryptographic or access-control vulnerability.
Treat as a normal bug fix. No urgent security response is warranted, but verify that pairing flows relying on visual MAC comparison now show the address in the same byte order as the host OS.
Security signals we found
UI display bug in security-relevant identifier (Bluetooth MAC address)
Potential user confusion during device pairing/verification
No change to access control, cryptography, or BLE protocol handling
Evidence from the diff
The patch changes _format_mac() in core/src/apps/homescreen/device_menu.py to call reversed(ble_addr) before formatting. The comment added explains that the internal representation uses reversed byte order. The only security-relevant angle is that a user comparing the on-screen MAC address to a host/phone Bluetooth listing could mismatch devices and pair with the wrong peer, but the commit itself does not change pairing logic, bonding policy, or any cryptographic operation.
Changed components
core/src/apps/homescreen/device_menu.pyInspect captured patch +2 / −1
diff --git a/core/src/apps/homescreen/device_menu.py b/core/src/apps/homescreen/device_menu.py
index 5bf048dfb..feb161c58 100644
--- a/core/src/apps/homescreen/device_menu.py
+++ b/core/src/apps/homescreen/device_menu.py
@@ -9,7 +9,8 @@ BLE_MAX_BONDS = 8
def _format_mac(ble_addr: bytes) -> str:
- return ":".join(f"{byte:02X}" for byte in ble_addr)
+ """Internal MAC address representation is using reversed byte order."""
+ return ":".join(f"{byte:02X}" for byte in reversed(ble_addr))
def _find_device(connected_addr: bytes | None, bonds: list[bytes]) -> int | None:
Why this scored 19/100
Community notes
Notes can correct, qualify, or add evidence to the AI analysis. Every note shown here has been validated by a human moderator.
The AI analysis stands alone for now. Submit a note if you can add evidence or important context.