SSL/TLS Certificate Lookup
Check a domain's SSL/TLS certificate — who issued it, when it expires, and whether the chain is trusted
advnet.cz
SSL/TLS Certificate
SSL/TLS Certificate for advnet.cz
Expired- Issued by (CA)
- Let's Encrypt
- Subject
- config.sferia.cz
- Valid from
- Dec 10, 2024
- Valid until
- Mar 10, 2025 (expired 541 days ago)
- Public key
- RSA 2048-bit
- Serial
- 03FB6EFBE294CBE89C045FD3E55A12DD4CD8
- SHA-256 fingerprint
- 84:37:93:32:8C:58:85:60:DF:EB:6C:7C:B7:7B:66:BA:9F:38:E6:0F:B1:C7:7D:77:23:04:3C:D0:D6:52:48:69
- Chain
- R11 → ISRG Root X1
Certificate Authority Authorization (CAA)
No CAA policy is published for this domain — any certificate authority may issue for it.
We've observed 1 previous certificate for this host. This certificate has been served since Aug 8, 2026.
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Uptime
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DNS changes
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TLS certificate
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