Bluetooth LE and BR/EDR secure pairing in Bluetooth Core Specification 2.1 through 5.2 may permit a nearby man-in-the-middle attacker to identify the Passkey used during pairing (in the Passkey authentication procedure) by reflection of the public key and the authentication evidence of the initiating device, potentially permitting this attacker to complete authenticated pairing with the responding device using the correct Passkey for the pairing session. The attack methodology determines the Passkey value one bit at a time.
https://kb.cert.org/vuls/id/799380
https://www.intel.com/content/www/us/en/security-center/advisory/intel-sa-00520.html
https://www.intel.com/content/www/us/en/security-center/advisory/intel-sa-00517.html
https://lists.debian.org/debian-lts-announce/2021/06/msg00019.html
https://lists.debian.org/debian-lts-announce/2021/06/msg00020.html
https://lists.debian.org/debian-lts-announce/2021/06/msg00022.html
Source: MITRE
Published: 2021-05-24
Updated: 2022-04-22
Type: CWE-287
Base Score: 4.3
Vector: AV:A/AC:M/Au:N/C:P/I:P/A:N
Impact Score: 4.9
Exploitability Score: 5.5
Severity: MEDIUM
Base Score: 4.2
Vector: CVSS:3.1/AV:A/AC:H/PR:N/UI:N/S:U/C:L/I:L/A:N
Impact Score: 2.5
Exploitability Score: 1.6
Severity: MEDIUM