CVE-2021-37577 (CVSS 6.8)

Description

Bluetooth LE and BR/EDR Secure Connections pairing and Secure Simple Pairing using the Passkey entry protocol in Bluetooth Core Specifications 2.1 through 5.3 may permit an unauthenticated man-in-the-middle attacker to identify the Passkey used during pairing by reflection of a crafted public key with the same X coordinate as the offered public key and by reflection of the authentication evidence of the initiating device, potentially permitting this attacker to complete authenticated pairing with the responding device using the correct Passkey for the pairing session. This is a related issue to CVE-2020-26558.

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CVSS v3.1 Score

6.8

MEDIUM

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

Weakness Type (CWE)

CWE-639 CWE-639

References

Other References

https://bluetooth.com https://www.bluetooth.com/learn-about-bluetooth/key-attributes/bluetooth-security/passkey-impersonation/ https://www.bluetooth.com/learn-about-bluetooth/key-attributes/bluetooth-security/reporting-security/

Frequently Asked Questions

What is CVE-2021-37577? +

Bluetooth LE and BR/EDR Secure Connections pairing and Secure Simple Pairing using the Passkey entry protocol in Bluetooth Core Specifications 2.1 through 5.3 may permit an unauthenticated man-in-the-middle attacker to identify the Passkey used during pairing by reflection of a crafted public key with the same X coordinate as the offered public key and by reflection of the authentication evidence of the initiating device, potentially permitting this attacker to complete authenticated pairing with the responding device using the correct Passkey for the pairing session. This is a related issue to CVE-2020-26558. It has a CVSS v3.1 base score of 6.8 (MEDIUM).

How severe is CVE-2021-37577? +

CVE-2021-37577 has a CVSS v3.1 score of 6.8 out of 10, rated MEDIUM. This is a medium-severity vulnerability that should be remediated as part of regular maintenance.

How do I check if I'm vulnerable to CVE-2021-37577? +

You can use Secably's free Website Scanner to check your website for known vulnerabilities. For infrastructure scanning, use the Port Scanner to identify exposed services that may be affected. Check the vendor advisories linked above for specific patch and version information.

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