SwissSign: S/MIME NCP non ASCII symbols in email and SAN field wrong coding

SwissSign AG identified a misissuance of 98 S/MIME NCP certificates due to incorrect encoding of non-ASCII characters in the Subject Alternative Name (SAN) field. This issue was discovered during an annual audit, which revealed that the SAN field did not conform to the required standards. The affected certificates were revoked before the deadline, and measures have been implemented to prevent future occurrences, including the introduction of a linter to catch such errors. The incident highlights the importance of compliance with RFC standards in certificate issuance.

1. 2023-09-01 S/MIME BR chapter 7.1.2.4 released, requiring compliance with RFC 5280.
2. 2023-12-02 First mis-issuance of affected certificates.
3. 2024-02-20 Last mis-issuance of affected certificates.
4. 2024-02-23 Activation of S/MIME linter to prevent further mis-issuance.
5. 2024-08-23 Revocation of all affected certificates completed.
6. 2024-09-06 Completion of test-coverage for non-ASCII characters.