Let's Encrypt is about to launch an IP certificate, although its validity period is only seven days, it still cannot prevent IP former holders from MiTM attacks within 7 days. I suggest that when issuing for an IP certificate, check if the current IP has valid certificates in CT. If so, require tha…

[image] hebbet: Reuse is 7 hours Not days I think they are commenting about the life of the cert itself, not reuse of the authorization. That is, person A gets a cert for an IP address. For whatever reason that IP is now controlled by person B. Person A's cert would still be valid for that…

Check valid certificates when issuing for IP certificates

Issuance Policy

Nekit December 16, 2025, 11:33am 18

"this week"

4 Likes

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Check valid certificates when issuing for IP certificates

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