CVE-2020-15802

MEDIUM

Bluetooth Core Specification < 5.1 - Unauthenticated Man-in-the-Middle via Cross Transport Key Derivation

Title source: llm
STIX 2.1

Exploitation Summary

EIP tracks 1 public exploit for CVE-2020-15802. PoCs published by francozappa.

AI-analyzed exploit summary This repository contains a proof-of-concept for the BLURtooth attack (CVE-2020-15802), which exploits Cross-Transport Key Derivation (CTKD) in Bluetooth Classic and Bluetooth Low Energy. The PoC demonstrates how an attacker can impersonate a device and overwrite pairing keys by downgrading the pairing procedure to Just Works.

Description

Devices supporting Bluetooth before 5.1 may allow man-in-the-middle attacks, aka BLURtooth. Cross Transport Key Derivation in Bluetooth Core Specification v4.2 and v5.0 may permit an unauthenticated user to establish a bonding with one transport, either LE or BR/EDR, and replace a bonding already established on the opposing transport, BR/EDR or LE, potentially overwriting an authenticated key with an unauthenticated key, or a key with greater entropy with one with less.

Exploits (1)

nomisec WORKING POC 19 stars
by francozappa · poc
https://github.com/francozappa/blur

This repository contains a proof-of-concept for the BLURtooth attack (CVE-2020-15802), which exploits Cross-Transport Key Derivation (CTKD) in Bluetooth Classic and Bluetooth Low Energy. The PoC demonstrates how an attacker can impersonate a device and overwrite pairing keys by downgrading the pairing procedure to Just Works.

Classification
Working Poc 95%
Attack Type
Auth Bypass
Complexity
Moderate
Reliability
Reliable
Target: Bluetooth devices supporting Bluetooth 4.2+ and Secure Connections
No auth needed
Prerequisites: Bluetooth devices supporting BT/BLE and CTKD · Linux machine with bluez and btmgmt tools · Physical proximity to target devices
devstral-2 · analyzed Feb 16, 2026 Full analysis →

References (3)

Core 3
Core References
Third Party Advisory, US Government Resource x_refsource_misc
https://www.kb.cert.org/vuls/id/589825

Scores

CVSS v3 5.9
EPSS 0.0714
EPSS Percentile 93.5%
Attack Vector NETWORK
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:H/A:N

Details

CWE
CWE-287
Status published
Products (1)
bluetooth/bluetooth_core_specification < 5.1
Published Sep 11, 2020
Tracked Since Feb 18, 2026