CVE-2024-5754Public exploit

Bluetooth encryption bypass via trusted HCI success status

Published Sep 13, 2024 · Updated Sep 17, 2025

Improper encryption-state validation in Zephyr RTOS 3.6 and earlier allows physically proximate attackers to bypass Bluetooth link encryption. In hci_encrypt_change, the host trusts a successful event error_code without checking evt->encrypt, so a malicious peripheral's rejected request is recorded as encrypted. The target must act as a Bluetooth Central and connect to the peripheral; affected host layers can then disclose or accept modified traffic over an unencrypted ACL.

CVSS severity8.2
High
EPSS probability0.31%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
Coverage for this vulnerability

See if you're affected

Explore vulnerability checks for your environment with Hinoki.

Book a demo

Summary

What happened

Improper encryption-state validation in Zephyr RTOS 3.6 and earlier allows physically proximate attackers to bypass Bluetooth link encryption. In hci_encrypt_change, the host trusts a successful event error_code without checking evt->encrypt, so a malicious peripheral's rejected request is recorded as encrypted. The target must act as a Bluetooth Central and connect to the peripheral; affected host layers can then disclose or accept modified traffic over an unencrypted ACL.

The record

CVE
CVE-2024-5754
Published
Sep 13, 2024
Updated
Sep 17, 2025
Vendor
Zephyr Project
Product
Zephyr RTOS
Classifications
CWE-807
Attack vector
adjacent
Privileges
unauthenticated

Timeline

How it unfolded

  1. Sep 13, 2024CVE publishedPublication date reported by the CVE source.
  2. Sep 17, 2025Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

Compare your product and version with the public record. A matching version still requires validation against your environment.

Is a vulnerable build present?

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

  1. Affected versionversion=* <=3.6

What conditions does exploitation require?

Attack vectoradjacent
Required privilegesunauthenticated

What is affected?

Zephyr Project · Zephyr RTOSversion=* <=3.6

Published CVSS scores

6.5NIST NVDCVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N
8.2Zephyr ProjectCVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:C/C:H/I:L/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
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitPublished

Weakness, pattern, technique

CWE-807Reliance on Untrusted Inputs in a Security Decision

Public exploit references

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

Technologies

Your stack

See the directory against your own environment.

Your stack

Check the software in your environment

Book a demo to see how Hinoki identifies affected software and validates exploitability in your environment.

Book a demo