CVE intelligence and bounded remediation

CVE-2021-31785 — Actions-Semi Ats2819P Firmware security vulnerability

Medium CVSS 6.5

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
Medium
CVSS
6.5 (3.1)
Published
2021-09-07
CISA KEV
Not currently listed
Ecosystem
operating-system
Weaknesses
CWE-667

Affected products

  • actions-semi / ats2819p_firmware
  • actions-semi / ats2815_firmware
  • actions-semi / ats2819_firmware
  • actions-semi / ats2819s_firmware
  • actions-semi / ats2819t_firmware

Matched remediation archetype

Race condition, TOCTOU, and lifecycle synchronization

This catalog composition supplies bounded fallback guidance. Explicitly reviewed curated workflows load with the complete record below.

Check exposure

  • Map concurrent actors, shared state, lock boundaries, signals, callbacks, retries, and check-then-use sequences in the affected path.
  • Determine whether untrusted users can influence timing, object names, filesystem state, or repeated state transitions.
  • Identify clustered and multi-process behavior that repository-local tests may not represent.

Remediate safely

  • Make the sensitive state transition atomic or protect it with a consistently ordered synchronization primitive.
  • Perform authorization and invariant checks on the same authoritative object and transaction used for the operation.
  • Use unique private resources, safe ownership transfer, and idempotent operations; add deterministic concurrency regression tests.

Authoritative sources

Complete CVE record and remediation plan

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