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Bugzilla #1752670
Certificate Misissuance
Let's Encrypt: TLS Using ALPN Allows Additional Identifiers in Challenge Certificate
RESOLVED
FIXED
Internet Security Research Group
AI Summary
Let's Encrypt encountered a compliance issue with the TLS-ALPN-01 challenge method, leading to the issuance of a certificate that included non-compliant Subject Alternative Names (SAN). Specifically, the SAN contained an IP address alongside the required dNSName, violating RFC 8737. Upon discovery, the certificate was revoked, and a fix was implemented to prevent future occurrences. All affected certificates were identified and revoked within five days of the incident.
Chronology
- Bug report received; initial response and investigation began.
- Fix deployed to production environment.
- All affected certificates revoked.
Participants
Jillian Karner
Aaron Wilson
External References
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