SSL/TLS Certificate Lookup
Check a domain's SSL/TLS certificate — who issued it, when it expires, and whether the chain is trusted
duo-lab.pl
SSL/TLS Certificate
SSL/TLS Certificate for duo-lab.pl
Hostname mismatch- Issued by (CA)
- cyber_Folks S.A.
- Subject
- *.damaslawek.pl
- Valid from
- Sep 24, 2026
- Valid until
- Apr 11, 2027 (154 days remaining)
- Public key
- RSA 4096-bit
- Serial
- 52B156D2769F7D00F51AD669AA5BC885
- SHA-256 fingerprint
- 99:71:DC:0B:E3:6B:9C:53:0A:4F:4D:51:AA:CB:DE:D4:40:93:56:D4:2B:49:4F:87:6B:48:FA:7D:88:BF:A7:B4
- Chain
- cyber_Folks → Certum Global Services CA SHA2 → Certum Trusted Network CA
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 Sep 28, 2026.
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DNS changes
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TLS certificate
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