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Bugzilla #1752452 Certificate Problem Report

Certainly: TLS Using ALPN TLS Version and OID

RESOLVED FIXED Certainly LLC
AI Summary

Certainly LLC faced a vulnerability related to the TLS-ALPN-01 validation method after being notified by Let’s Encrypt about a related issue. They promptly disabled the affected validations and revoked all certificates that relied on this method. The incident was declared on January 25, 2022, and a total of 337,621 certificates were identified as potentially problematic. A comprehensive incident report was prepared, detailing the timeline of actions taken and the steps to prevent future occurrences.

Model: gpt-4o-mini Generated: 2026-06-13 21:24 UTC Confidence: 1.00
Chronology
  1. Incident declared after assessing vulnerability
  2. All affected certificates revoked
  3. Incident remediation plan finalized
  4. Remediation of the incident completed
Participants
Wayne Thayer Charles Wang
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