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Bugzilla #1966515 Certificate Problem Report

Let's Encrypt: Issuance for Invalid Internationalized Domain Name

RESOLVED INVALID Internet Security Research Group
AI Summary

This case discusses the issuance of a certificate by Let's Encrypt that contained an Internationalized Domain Name (IDN) with a disallowed Unicode character (U+200E, LEFT-TO-RIGHT MARK). While the certificate technically complies with the Baseline Requirements due to an exception allowing certain Punycode representations, it raises significant concerns regarding user safety and potential domain spoofing. The discussion concluded that the issuance does not violate any current policies, but it highlights the need for clearer guidelines to prevent misuse of such characters in domain names.

Model: gpt-4o-mini Generated: 2026-06-13 21:19 UTC Confidence: 0.90
Chronology
  1. Preliminary report filed by Let's Encrypt.
  2. Community discussion on the compliance of the certificate.
  3. Support for closing the bug as INVALID expressed by Chrome Root Program.
  4. Mozilla expresses concerns about user safety and trust.
  5. Final call for comments before closure.
Participants
Aaron Gable Dimitris Zacharopoulos Chrome Root Program Mozilla
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