CVE-2021-3658

Nearby adapter exposure via persisted discoverable state

Published Mar 2, 2022 · Updated Apr 15, 2026

Incorrect authorization in BlueZ before 5.61 allows physically proximate attackers to reach an adapter left discoverable after power-up. In src/adapter.c, bluetoothd persists a temporary Discoverable state set by a discovery client and restores that state when the adapter powers up. Exposure requires Bluetooth radio proximity and an adapter powered down while temporarily discoverable; the documented consequence is discoverability, not data alteration or service interruption.

CVSS severity6.5
Medium
EPSS probability0.79%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Incorrect authorization in BlueZ before 5.61 allows physically proximate attackers to reach an adapter left discoverable after power-up. In src/adapter.c, bluetoothd persists a temporary Discoverable state set by a discovery client and restores that state when the adapter powers up. Exposure requires Bluetooth radio proximity and an adapter powered down while temporarily discoverable; the documented consequence is discoverability, not data alteration or service interruption.

The record

CVE
CVE-2021-3658
Published
Mar 2, 2022
Updated
Apr 15, 2026
Vendor
BlueZ Project
Product
BlueZ
Classifications
CWE-863, T1046
Attack vector
adjacent
Privileges
unauthenticated

Timeline

How it unfolded

  1. Mar 2, 2022CVE publishedPublication date reported by the CVE source.
  2. Apr 15, 2026Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

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Is a vulnerable build present?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=Fixedin - 5.61 and above.

What conditions does exploitation require?

Attack vectoradjacent
Required privilegesunauthenticated

What is affected?

BlueZ Project · BlueZversion=Fixedin - 5.61 and above.

Published CVSS scores

6.5NVDCVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N
6.5CISA-ADPCVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N
4.6SUSECVSS:3.1/AV:A/AC:H/PR:N/UI:R/S:U/C:L/I:L/A:L
3.3NVDAV:A/AC:L/Au:N/C:P/I:N/A:N

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

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No observations available

Sep 9, 2026Sep 15, 2026
Latest reporting daySep 15, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectoradjacent
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-863Incorrect Authorization
T1046Network Service Discovery

Public exploit references

No public exploit references are available in this record.

Labels summarize the accepted research assessment. They do not indicate a test against your environment.

Technologies

Your stack

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Your stack

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