CVE-2021-34147
The Bluetooth Classic implementation in the Cypress WICED BT stack through 2.9.0 for CYW20735B1 does not properly handle the reception of a malformed LMP timing accuracy response followed by multiple reconnections to the link slave, allowing attackers…
Does this matter?
Lower severity and a low EPSS score (0.58%). Track it; it rarely justifies an emergency change on its own.
Description
The Bluetooth Classic implementation in the Cypress WICED BT stack through 2.9.0 for CYW20735B1 does not properly handle the reception of a malformed LMP timing accuracy response followed by multiple reconnections to the link slave, allowing attackers to exhaust device BT resources and eventually trigger a crash via multiple attempts of sending a crafted LMP timing accuracy response followed by a sudden reconnection with a random BDAddress.
- CVSS 3.1
- 6.5 MEDIUMCVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
- EPSS
- 0.58% probability · 46th percentile
- CISA KEV
- Not listed
- Affected
- cypress/wireless internet connectivity for embedded devices
- Source
- cve@mitre.org
References
- https://dl.packetstormsecurity.net/papers/general/braktooth.pdfTechnical Description, Third Party Advisory
- https://www.cypress.com/documentation/datasheets/cyw20735b1-single-chip-bluetooth-transceiver-wireless-input-devicesVendor Advisory
- https://dl.packetstormsecurity.net/papers/general/braktooth.pdfTechnical Description, Third Party Advisory
- https://www.cypress.com/documentation/datasheets/cyw20735b1-single-chip-bluetooth-transceiver-wireless-input-devicesVendor Advisory
Source: NVD record, EPSS from FIRST.org, KEV from CISA. Refreshed daily.