CVE-2021-34144

The Bluetooth Classic implementation in the Zhuhai Jieli AC6366C BT SDK through 0.9.1 does not properly handle the reception of truncated LMP_SCO_Link_Request packets while no other BT connections are active, allowing attackers in radio range to prevent new BT connections (disabling the AB5301A inquiry and page scan procedures) via a crafted LMP packet. The user needs to manually perform a power cycle (restart) of the device to restore BT connectivity.

Published: 2021-09-07 Last update: 2024-11-21 Assigner: [email protected] Source: [email protected]

Conclusion & alert: CVE-2021-34144 is rated Moderate Risk (42.9/100): CVSS Medium severity, with low exploitation likelihood (EPSS 0.67%). Mandatory action: Review affected assets and schedule remediation.

Risk is dynamic; we continuously reassess and refresh what is shown on this page as upstream context changes.

Exploit prediction scoring system (EPSS) score for CVE-2021-34144

EPSS lead: Daily EPSS estimates relative likelihood of exploitation; percentile ranks this CVE among scored vulnerabilities (higher = more severe relative rank).

# Date Old EPSS score New EPSS score Delta (New - Old)
1 2026-06-15 0.14% 0.67% +0.53%
2 2025-03-30 0.20% 0.14% -0.06%
3 2025-03-29 0.20%

Full EPSS history (8 records total)

Common vulnerability scoring system (CVSS) metrics for CVE-2021-34144

CVSS metrics for this CVE.

Base score Version Severity Vector Exploitability Impact Score source
6.5 3.1 MEDIUM
CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H Click to expand
Attack vector (AV:A)
Attacker has to be nearby on the network—same office, same link, that vibe—not the whole wide internet.
Attack complexity (AC:L)
Once they can reach the bug, pulling it off is straightforward—no weird race conditions or rare setup.
Privileges required (PR:N)
No account or special rights needed—anonymous or random user is enough.
User interaction (UI:N)
Nobody has to click “OK” or open a trap file; it can work without a victim helping.
Scope (S:U)
Damage stays in the same “trust bubble” as the broken component—no big spill into unrelated systems.
Confidentiality (C:N)
Doesn’t really leak secrets in a meaningful way.
Integrity (I:N)
Data isn’t meaningfully altered or forged.
Availability (A:H)
Could take the service down hard or make it unusable for people who depend on it.
2.8 3.6 [email protected]
3.3 2.0 LOW
AV:A/AC:L/Au:N/C:N/I:N/A:P Click to expand
Access vector (AV:A)
Requires access to an adjacent network segment.
Access complexity (AC:L)
Exploitation conditions are straightforward and predictable.
Authentication (AU:N)
No authentication is required.
Confidentiality impact (C:N)
No confidentiality impact.
Integrity impact (I:N)
No integrity impact.
Availability impact (A:P)
Partial availability impact.
6.5 2.9 [email protected]

Weakness enumeration for CVE-2021-34144

Affected software / configurations for CVE-2021-34144

Vendor Product Version Raw CPE
zh-jieli fw-ac63_bt_sdk <= 0.9.1 cpe:2.3:o:zh-jieli:fw-ac63_bt_sdk:*:*:*:*:*:*:*:*

References for CVE-2021-34144

cvelogic Threat Intelligence