SwissSign: Two certs issued with same issuer and serial number

This case involves SwissSign, which issued two certificates with the same issuer and serial number. The issue was identified by Mozilla when it was noted that both certificates had different expiration dates but shared the same serial number. SwissSign acknowledged the misissuance, explaining that the certificates were incorrectly issued in 2009 due to a flaw in their CA software. They have since revoked the problematic certificates and updated their processes to prevent similar issues in the future. The last certificate was revoked on November 11, 2017, and the case has been marked as resolved.

1. 2017-09-29 Mozilla identifies misissuance of two certificates with the same serial number.
2. 2017-10-11 SwissSign revokes the last problematic certificate.

1. 2017-09-29 Mozilla representative — Identified two certificates with the same serial number and requested SwissSign to investigate.
2. 2017-10-02 SwissSign AG — SwissSign confirmed the misissuance and explained the circumstances.
3. 2017-10-10 SwissSign AG — Provided a timeline of actions taken in response to the misissuance.
4. 2017-10-11 SwissSign AG — Confirmed revocation of the last problematic certificate.
5. 2017-10-12 Mozilla representative — Verified the revocation status and suggested closing the bug.