{"id":"CVE-2021-31785","aliases":["EUVD-2021-18666","GHSA-8235-3268-fjf9"],"status":"published","title":"The Bluetooth Classic implementation on Actions ATS2815 and ATS2819 chipsets does not properly...","description":"The Bluetooth Classic implementation on Actions ATS2815 and ATS2819 chipsets does not properly handle the reception of multiple LMP_host_connection_req packets, allowing attackers in radio range to trigger a denial of service (deadlock) of the device via crafted LMP packets. Manual user intervention is required to restart the device and restore Bluetooth communication.","severity":{"version":"3.1","score":6.5,"vector":"CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H","level":"medium","assessor":"primary","from":"nvd"},"epss":{"day":"2026-11-10","score":0.00446,"percentile":0.39136,"model":"v2026.06.15"},"facts":{"in_kev":false,"known_exploited":false,"public_exploit":false,"fix_available":false},"cwes":["CWE-667"],"published":"2021-09-07T06:07:39Z","modified":"2026-06-17T03:52:13Z","products":[{"vendor":"actions-semi","product":"ats2815_firmware"},{"vendor":"actions-semi","product":"ats2819_firmware"},{"vendor":"actions-semi","product":"ats2819p_firmware"},{"vendor":"actions-semi","product":"ats2819s_firmware"},{"vendor":"actions-semi","product":"ats2819t_firmware"}],"references":[{"url":"https://www.actions-semi.com/index.php?id=3581\u0026siteId=4","tags":["x_refsource_MISC","x_transferred","Broken Link","Vendor Advisory"]},{"url":"https://launchstudio.bluetooth.com/ListingDetails/76427","tags":["x_refsource_MISC","x_transferred","Third Party Advisory"]},{"url":"https://dl.packetstormsecurity.net/papers/general/braktooth.pdf","tags":["x_refsource_MISC","x_transferred","Technical Description","Third Party Advisory"]},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2021-31785"},{"url":"https://github.com/advisories/GHSA-8235-3268-fjf9"}],"sources":{"cve":[{"id":"CVE-2021-31785","description":"The Bluetooth Classic implementation on Actions ATS2815 and ATS2819 chipsets does not properly handle the reception of multiple LMP_host_connection_req packets, allowing attackers in radio range to trigger a denial of service (deadlock) of the device via crafted LMP packets. Manual user intervention is required to restart the device and restore Bluetooth communication.","status":"published","published":"2021-09-07T06:07:39Z","modified":"2024-08-03T23:10:29.927Z","updated_at":"2026-11-02T14:33:05.665371Z"}],"euvd":[{"id":"EUVD-2021-18666","description":"The Bluetooth Classic implementation on Actions ATS2815 and ATS2819 chipsets does not properly handle the reception of multiple LMP_host_connection_req packets, allowing attackers in radio range to trigger a denial of service (deadlock) of the device via crafted LMP packets. Manual user intervention is required to restart the device and restore Bluetooth communication.","status":"published","published":"2021-09-07T06:07:39Z","modified":"2024-08-03T23:10:29Z","updated_at":"2026-11-03T03:24:38.423371Z"}],"ghsa":[{"id":"GHSA-8235-3268-fjf9","title":"The Bluetooth Classic implementation on Actions ATS2815 and ATS2819 chipsets does not properly...","description":"The Bluetooth Classic implementation on Actions ATS2815 and ATS2819 chipsets does not properly handle the reception of multiple LMP_host_connection_req packets, allowing attackers in radio range to trigger a denial of service (deadlock) of the device via crafted LMP packets. Manual user intervention is required to restart the device and restore Bluetooth communication.","status":"published","published":"2022-05-24T19:13:16Z","modified":"2023-01-30T05:01:56Z","cvss":[{"version":"3.1","score":6.5,"vector":"CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H","level":"medium"}],"cwes":["CWE-667"],"updated_at":"2026-11-02T14:46:31.204916Z"}],"nvd":[{"id":"CVE-2021-31785","description":"The Bluetooth Classic implementation on Actions ATS2815 and ATS2819 chipsets does not properly handle the reception of multiple LMP_host_connection_req packets, allowing attackers in radio range to trigger a denial of service (deadlock) of the device via crafted LMP packets. Manual user intervention is required to restart the device and restore Bluetooth communication.","status":"published","published":"2021-09-07T07:15:07.143Z","modified":"2026-06-17T03:52:13.98Z","cvss":[{"version":"3.1","score":6.5,"vector":"CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H","level":"medium","assessor":"primary"},{"version":"2.0","score":6.1,"vector":"AV:A/AC:L/Au:N/C:N/I:N/A:C","level":"medium","assessor":"primary"}],"cwes":["CWE-667"],"updated_at":"2026-11-02T14:06:58.05696Z"}]}}