CVE-2021-34150

The Bluetooth Classic implementation on Bluetrum AB5301A devices with unknown firmware versions does not properly handle the reception of oversized DM1 LMP 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: 2026-06-16 Assigner: [email protected] Source: [email protected]

Conclusion & alert: CVE-2021-34150 is rated Low Risk (37.2/100): CVSS Medium severity, with low exploitation likelihood (EPSS 0.40%). Mandatory action: Monitor for updates and reassess as exploit intelligence or EPSS changes.

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-2021-34150

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 0.13% 0.40% +0.27%
2 2025-04-16 0.24% 0.13% -0.11%
3 2025-03-30 0.24%

Full EPSS history (10 records total)

Common vulnerability scoring system (CVSS) metrics for CVE-2021-34150

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-2021-34150

Affected software / configurations for CVE-2021-34150

Vendor Product Version Raw CPE
bluetrum ab5301a_firmware cpe:2.3:o:bluetrum:ab5301a_firmware:-:*:*:*:*:*:*:*

References for CVE-2021-34150

URL Tags
http://www.bluetrum.com/product/ab5301a.html Product Vendor Advisory
https://dl.packetstormsecurity.net/papers/general/braktooth.pdf Technical Description Third Party Advisory
cvelogic Threat Intelligence