Peer impersonation via Passkey bit recovery
Published Jan 12, 2021 · Updated Oct 8, 2024
Bluetooth authentication bypass in affected Microsoft Windows releases allows physically proximate attackers to impersonate a pairing peer. The Passkey Entry exchange accepts crafted round-by-round responses that reveal each random passkey bit, then accepts those bits within the same pairing session. The attacker must be within wireless range of two vulnerable devices starting Passkey pairing; exploitation authenticates the responder to the attacker as an encrypted peer, not to the intended initiator.
Summary
What happened
Bluetooth authentication bypass in affected Microsoft Windows releases allows physically proximate attackers to impersonate a pairing peer. The Passkey Entry exchange accepts crafted round-by-round responses that reveal each random passkey bit, then accepts those bits within the same pairing session. The attacker must be within wireless range of two vulnerable devices starting Passkey pairing; exploitation authenticates the responder to the attacker as an encrypted peer, not to the intended initiator.
The record
- CVE
- CVE-2021-1638
- Published
- Jan 12, 2021
- Updated
- Oct 8, 2024
- Vendor
- Microsoft
- Product
- Windows Server 2019
- Classifications
- T1557
- Attack vector
- adjacent
- Privileges
- unauthenticated
Timeline
How it unfolded
- Jan 12, 2021CVE publishedPublication date reported by the CVE source.
- Oct 8, 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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- Affected versionversion=10.0.0 <publication
What conditions does exploitation require?
What is affected?
Published CVSS scores
CVSS describes severity. EPSS estimates exploitation probability.
Attacks
What attackers are doing with it
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Weakness, pattern, technique
Public exploit references
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Technologies
Your stack
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Your stack
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