CVE-2021-37577

CVE-2021-37577 is a medium-severity vulnerability with a CVSS 3.x base score of 6.8. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-639.

Key facts

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.

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.
How severe is CVE-2021-37577?
CVE-2021-37577 has a CVSS 3.x base score of 6.8, rated medium severity. It is exploitable over local access with low attack complexity, requires low privileges and user interaction. Impact on confidentiality is high, integrity high, and availability low.
Is CVE-2021-37577 being actively exploited?
It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (15th percentile), an estimate of the probability of exploitation in the next 30 days.
How do I fix CVE-2021-37577?
Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
Does CVE-2021-37577 have an EU (EUVD) identifier?
Yes. CVE-2021-37577 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2021-24138.
When was CVE-2021-37577 published?
CVE-2021-37577 was published on 2024-10-01 and last updated on 2026-06-17.

References

Other CWE-639 (Authorization Bypass Through User-Controlled Key (IDOR)) vulnerabilities

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