CVE-2021-0129

Authenticated GATT data disclosure via unchecked permissions

Published Jun 9, 2021 · Updated Aug 3, 2024

Improper access control in BlueZ before 5.58 allows adjacent authenticated users to read protected GATT characteristic data. The check_permissions function fails to enforce the secure permission, leaving a BLE connection at its prior security level when a characteristic requires Security Mode 1 Level 4. A nearby user with an established BLE connection can access such characteristics without the required secure pairing, authentication, and 128-bit encryption.

CVSS severity6.4
Medium
EPSS probability0.83%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Improper access control in BlueZ before 5.58 allows adjacent authenticated users to read protected GATT characteristic data. The check_permissions function fails to enforce the secure permission, leaving a BLE connection at its prior security level when a characteristic requires Security Mode 1 Level 4. A nearby user with an established BLE connection can access such characteristics without the required secure pairing, authentication, and 128-bit encryption.

The record

CVE
CVE-2021-0129
Published
Jun 9, 2021
Updated
Aug 3, 2024
Vendor
BlueZ Project
Product
BlueZ
Classifications
Unavailable
Attack vector
adjacent
Privileges
authenticated

Timeline

How it unfolded

  1. Jun 9, 2021CVE publishedPublication date reported by the CVE source.
  2. Aug 3, 2024Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

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Is a vulnerable build present?

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  1. Affected versionversion=See references

What conditions does exploitation require?

Attack vectoradjacent
Required privilegesauthenticated

What is affected?

BlueZ Project · BlueZversion=See references

Published CVSS scores

2.7NIST NVDAV:A/AC:L/Au:S/C:P/I:N/A:N
6.4Intel CorporationCVSS:3.1/AV:A/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:N
5.7NIST NVDCVSS:3.1/AV:A/AC:L/PR:L/UI:N/S:U/C:H/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.

Daily unique IPsNo honeypot observations are available for this CVE in the selected window.

No observations available

Sep 10, 2026Sep 16, 2026
Latest reporting daySep 16, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectoradjacent
Privilegesauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

No sourced classifications are available.

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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