SSL/TLS Certificate Lookup
Check a domain's SSL/TLS certificate — who issued it, when it expires, and whether the chain is trusted
isy-schule.app
SSL/TLS Certificate
SSL/TLS Certificate for isy-schule.app
Expired- Issued by (CA)
- Sectigo Limited
- Subject
- *.alfion.net
- Valid from
- Sep 18, 2024
- Valid until
- Jul 15, 2025 (expired 388 days ago)
- Public key
- RSA 4096-bit
- Serial
- 77C0B3C9BE8CCDECA47425CDB38D5D99
- SHA-256 fingerprint
- 49:CC:A6:98:7C:90:A4:10:06:60:54:D7:A8:44:D8:1B:FB:BD:0C:58:65:28:7A:CA:F8:4F:77:09:A6:36:16:B5
- Chain
- Sectigo RSA Domain Validation Secure Server CA → USERTrust RSA Certification Authority
Certificate Authority Authorization (CAA)
No CAA policy is published for this domain — any certificate authority may issue for it.
This certificate has been served since Aug 4, 2026.
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TLS certificate
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