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Bugzilla #1888104 Certificate Misissuance

Disig: TLS certificate with basicConstraints not marked as critical

RESOLVED FIXED Disig, a.s.
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AI Summary

Disig, a.s. was notified about a TLS certificate and a corresponding precertificate that did not have the basicConstraints extension marked as critical, violating TLS BR 7.1.2.7.6. Following this discovery, Disig revoked the affected certificate on March 29, 2024, and issued a new compliant certificate. An incident report was prepared detailing the timeline and impact of the issue, which included identifying additional affected certificates. Disig has since implemented zlint into their production system to prevent future occurrences of similar compliance issues. The case is now considered resolved.

Model: gpt-4o-mini Generated: 2026-06-13 21:21 UTC Revised: 2026-06-16 18:35 UTC Confidence: 0.90 24 comments
Chronology
  1. Disig notified about non-compliance with basicConstraints extension in TLS certificate.
  2. Affected certificate revoked and new compliant certificate issued.
  3. Disig implemented zlint into their production CA system.
Thread Activity
  1. Disig, a.s. — Disig has been notified about a leaf certificate with basicConstraints extension that is not marked as critical.
  2. Disig, a.s. — Certificate was revoked on March 29, 2024, and a new certificate has been issued.
  3. Disig, a.s. — Incident report issued detailing the non-compliance and corrective actions taken.
  4. Disig, a.s. — Successfully implemented zlint into the production CA system.
  5. Disig, a.s. — Disig considers the subject of this bug to be resolved.
Participants
Disig, a.s. Mozilla representative Community commenter
External References
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