Cyber Resilience

CVE-2021-40855

Critical

Published: 21 January 2022

Published
21 January 2022
Modified
21 November 2024
KEV Added
Patch
CVSS Score v3.1 9.8 CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
EPSS Score 0.0027 50.2th percentile
Risk Priority 20 60% EPSS · 20% KEV · 20% CVSS

Summary

CVE-2021-40855 is a critical-severity Improper Certificate Validation (CWE-295) vulnerability in Europa Technical Specifications For Digital Covid Certificates. Its CVSS base score is 9.8 (Critical).

Operationally, ranked in the top 49.8% of CVEs by exploit likelihood; it is not currently listed in the CISA KEV catalog.

EU & UK References

Vulnerability details

The EU Technical Specifications for Digital COVID Certificates before 1.1 mishandle certificate governance. A non-production public key certificate could have been used in production.

CWE(s)

Related Threats

No named actor attribution yet. ATT&CK technique mapping in progress for this CVE.

Affected Assets

europa
technical specifications for digital covid certificates
≤ 1.1

Mitigating Controls

Likely Mitigating Controls AI

Per-CVE control mapping for this CVE has not run yet; the list below is derived from the weakness types (CWEs) cited in the NVD entry.

addresses: CWE-295

When certificates are used to establish component provenance, the control requires correct certificate validation procedures.

addresses: CWE-295

Mandates approved trust anchors and issuance policies, directly preventing acceptance of unvalidated or untrusted certificates.

addresses: CWE-295

Correct system time is required for proper enforcement of certificate notBefore/notAfter dates and time-based revocation checks.

References