CVE-2021-31611: Zh-Jieli AC6901 Firmware

Medium severity, CVSS 5.7. EPSS: 0.4% chance of exploitation in the next 30 days.

The Bluetooth Classic implementation on Zhuhai Jieli AC690X and AC692X devices does not properly handle an out-of-order LMP Setup procedure that is followed by a malformed LMP packet, allowing attackers in radio range to deadlock a device via a crafted LMP packet. The user needs to manually reboot the device to restore communication.

Affected products

• Zh-Jieli AC6901 Firmware: affected versions not specified
• Zh-Jieli AC6921 Firmware: affected versions not specified
• Zh-Jieli AC6925 Firmware: affected versions not specified
• Zh-Jieli AC6926 Firmware: affected versions not specified
• Zh-Jieli AC6928 Firmware: affected versions not specified

Published 2021-09-07. Last modified 2026-06-17.