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Fencer Intel
critical 9.8

CVE-2021-40855 json

The EU Technical Specifications for Digital COVID Certificates before 1.1 mishandle certificate governance.

published 4y ago modified 4mo ago also EUVD-2021-28011

cvss
9.8
version 3.1, NVD
cisa kev
Not listed
not in CISA's catalog
epss
0.7%
EPSS 0.7% chance of exploitation in 30 days, percentile 51%
public exploits
0
none known

Summary

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.

Patch / fix

  • europa technical_specifications_for_digital_covid_certificates 1.1

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Exploit prediction

0.66% chance of exploitation in the next 30 days, higher than 51% of all scored CVEs (FIRST EPSS, 2026-11-09).

CVSS scores

assigned by version score vector
NVD 3.1 9.8 CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
NVD 2.0 7.5 AV:N/AC:L/Au:N/C:P/I:P/A:P

Classification

Weakness
  • CWE-295 Improper Certificate Validation

References

Sources

Fencer Intel keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.