CVE-2021-37577

Pairing impersonation via reflected public key

Published Oct 1, 2024 · Updated Nov 15, 2024

Bluetooth Core Specifications 2.1 through 5.3 allow man-in-the-middle attackers to recover pairing passkeys and impersonate devices. During Passkey Entry pairing, a vulnerable implementation accepts a peer public key that reuses its own X coordinate and reflects authentication evidence, exposing the session passkey. An attacking device must be within wireless range of two vulnerable devices as they begin pairing or bonding with Passkey Entry selected.

CVSS severity6.8
Medium
EPSS probability0.24%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Bluetooth Core Specifications 2.1 through 5.3 allow man-in-the-middle attackers to recover pairing passkeys and impersonate devices. During Passkey Entry pairing, a vulnerable implementation accepts a peer public key that reuses its own X coordinate and reflects authentication evidence, exposing the session passkey. An attacking device must be within wireless range of two vulnerable devices as they begin pairing or bonding with Passkey Entry selected.

The record

CVE
CVE-2021-37577
Published
Oct 1, 2024
Updated
Nov 15, 2024
Vendor
Unknown vendor
Product
Unknown product
Classifications
CWE-639, T1557
Attack vector
adjacent
Privileges
unauthenticated

Timeline

How it unfolded

  1. Oct 1, 2024CVE publishedPublication date reported by the CVE source.
  2. Nov 15, 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?

Affected buildAffected product and version details are unavailable.

What conditions does exploitation require?

Attack vectoradjacent
Required privilegesunauthenticated

What is affected?

Affected products and versions are unavailable in this record.

Published CVSS scores

6.8CISACVSS:3.1/AV:L/AC:L/PR:L/UI:R/S:U/C:H/I:H/A:L

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-639Authorization Bypass Through User-Controlled Key
T1557Adversary-in-the-Middle

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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