tls-sni challenge disabled [Identified] Update regarding TLS-SNI validation can be found here: 2018.01.09 Issue with TLS-SNI-01 and Shared Hosting Infrastructure [Investigating] The tls-sni challenge has been disabled due to strong credibility of a vulnerability report.

Strong credibility of a vulnerability with TLS-SNI

tdelmas October 9, 2018, 10:17am 2

Yes, it was posted there:

Topic		Replies	Views
TLS-SNI challenges disabled for most new issuance API Announcements	4	17957	January 18, 2018
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