CVE-2021-31615: Bluetooth Core Specification

Medium severity, CVSS 5.3. EPSS: 0.4% chance of exploitation in the next 30 days.

Unencrypted Bluetooth Low Energy baseband links in Bluetooth Core Specifications 4.0 through 5.2 may permit an adjacent device to inject a crafted packet during the receive window of the listening device before the transmitting device initiates its packet transmission to achieve full MITM status without terminating the link. When applied against devices establishing or using encrypted links, crafted packets may be used to terminate an existing link, but will not compromise the confidentiality or integrity of the link.

Affected products

• Bluetooth Bluetooth Core Specification: from 4.0, up to and including 5.2

Published 2021-06-25. Last modified 2026-06-17.