The Bluetooth Low Energy peripheral implementation on Texas Instruments SIMPLELINK-CC2640R2-SDK through 3.30.00.20 and BLE-STACK through 1.5.0 before Q4 2019 for CC2640R2 and CC2540/1 devices does not properly restrict the advertisement connection request packet on reception, allowing attackers in radio range to cause a denial of service (crash) via a crafted packet.