Affected Products and Remediation
Most COROS watches and bike computers (WLAN firmware download functionality); tested version: PACE 3 ≤ 3.0808.0. Remediation: update the watch firmware to the official security patch version.
Vulnerability Description and Impact
The watch uses unencrypted HTTP to download firmware files over WLAN, leaving the communication unencrypted. An attacker on the same network can eavesdrop on the downloaded content and carry out a man-in-the-middle attack.
Mitigation Measures
Update your watch firmware to the latest version and use a trusted network for firmware updates. Do not obtain or install firmware through untrusted networks or unofficial channels.
Acknowledgments
We thank the following researcher for their contribution to product security:
- Moritz Abrell (SySS GmbH)
Revision History
v1.0 ｜ 2026-10-13