← Internet Security Research Group cases
Bugzilla #1319609 Certificate Misissuance

Let's Encrypt: certs issued contrary to CPS due to incomplete blocklist

RESOLVED Internet Security Research Group
AI Summary

This case addresses a misissuance of certificates by Let's Encrypt due to an incomplete blocklist caused by a bug in their issuance script. The issue was identified and resolved, with all affected certificates revoked. The incident highlighted the importance of compliance with the Certification Practice Statement (CPS) and the need for improved testing and policy review. Mozilla has determined that no further action is necessary as the CA has taken appropriate steps to rectify the situation.

Model: gpt-4o-mini Generated: 2026-06-13 11:59 UTC Confidence: 0.95
Chronology
  1. Problem with issuance blocklist identified and fixed.
  2. Case resolved with all affected certificates revoked.
Participants
Kathleen Wilson Gervase Markham jaas@kflag.net
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