Vulnerability in Cypress Cyw20735b1

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 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.

EPSS: 0.006 (44.3th percentile) — read the EPSS interpretation.

CVSS v3 metric

CVSS v3 base score 6.5 (Medium). Vector: CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H.

Affected products

Public proof-of-concept exploits

References

Frequently asked questions

What is CVE-2021-34147?
CVE-2021-34147 is a medium-severity vulnerability in Cypress Cyw20735b1. CVSS score: 6.5/10. Published 2021-09-07.
How severe is CVE-2021-34147?
Medium severity. CVSS v3 base score is 6.5 out of 10.
Is CVE-2021-34147 known to be exploited?
4 public proof-of-concept repositories are indexed. Not currently listed in the CISA KEV catalog.