FNMT: Issuance of certificate using keys previously reported as compromised

On January 23, 2026, FNMT-RCM was informed of a TLS certificate mis-issuance due to the use of a previously revoked private key that had suffered a key compromise. An investigation revealed that three certificates were affected, with one still active at the time of the incident. The affected certificate was revoked within 24 hours, and FNMT has committed to improving its monitoring processes to prevent future occurrences. The incident was reported by a third party, highlighting the need for enhanced verification and automated checks.

1. 2026-01-23 Incident reported by third party
2. 2026-01-25 Preliminary Incident Report opened
3. 2026-02-06 Full Incident Report submitted
4. 2026-02-20 Report closure summary provided