How severe is CVE-2020-26556?

CVE-2020-26556 has a CVSS 3.x base score of 7.5, rated high severity. It is exploitable over an adjacent network with high attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.

Is CVE-2020-26556 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (56th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2020-26556?

CVE-2020-26556 primarily affects Bluetooth Bluetooth Core Specification. In total, 3 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2020-26556?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.

When was CVE-2020-26556 published?

CVE-2020-26556 was published on 2021-05-24 and last updated on 2026-06-17.

CVE-2020-26556

CVE-2020-26556 is a high-severity vulnerability in Bluetooth Bluetooth Core Specification with a CVSS 3.x base score of 7.5. 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-307.

Key facts

Severity: High (CVSS 3.x base score 7.5)
CVSS v2: 2.9
EPSS exploit prediction: 1% (56th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-307
Affected product: Bluetooth Bluetooth Core Specification
Published: 2021-05-24
Last modified: 2026-06-17

Description

Mesh Provisioning in the Bluetooth Mesh profile 1.0 and 1.0.1 may permit a nearby device, able to conduct a successful brute-force attack on an insufficiently random AuthValue before the provisioning procedure times out, to complete authentication by leveraging Malleable Commitment.

Frequently asked questions

What is CVE-2020-26556?: Mesh Provisioning in the Bluetooth Mesh profile 1.0 and 1.0.1 may permit a nearby device, able to conduct a successful brute-force attack on an insufficiently random AuthValue before the provisioning procedure times out, to complete authentication by leveraging Malleable Commitment.
How severe is CVE-2020-26556?: CVE-2020-26556 has a CVSS 3.x base score of 7.5, rated high severity. It is exploitable over an adjacent network with high attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.
Is CVE-2020-26556 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (56th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2020-26556?: CVE-2020-26556 primarily affects Bluetooth Bluetooth Core Specification. In total, 3 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2020-26556?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.
When was CVE-2020-26556 published?: CVE-2020-26556 was published on 2021-05-24 and last updated on 2026-06-17.

References

Affected products (3)

cpe:2.3:a:bluetooth:bluetooth_core_specification:*:*:*:*:*:*:*:*
cpe:2.3:a:bluetooth:mesh_profile:1.0.0:*:*:*:*:*:*:*
cpe:2.3:a:bluetooth:mesh_profile:1.0.1:*:*:*:*:*:*:*

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