SSL/TLS Certificate Lookup
Check a domain's SSL/TLS certificate — who issued it, when it expires, and whether the chain is trusted
lumen1.co.kr
SSL/TLS Certificate
SSL/TLS Certificate for lumen1.co.kr
Valid- Issued by (CA)
- Sectigo Limited
- Subject
- lumen1.co.kr
- Valid from
- Feb 20, 2026
- Valid until
- Feb 20, 2027 (166 days remaining)
- Public key
- RSA 2048-bit
- Serial
- 01960926580E84EF25A80A427CE27358
- SHA-256 fingerprint
- 5C:CA:67:0B:52:DA:B7:47:32:ED:64:9F:CC:43:DC:A8:FD:C2:C4:BB:5F:B3:F1:E3:4F:72:EB:8C:DC:53:85:92
- 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 26, 2026.
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Uptime
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DNS changes
We watch NS, MX, CAA, DNSSEC, CNAME and A/AAAA records, and identify the host, network, and ASN behind them, so a real migration or hijack stands out from routine noise.
TLS certificate
We warn you 30, 14, 7, and 1 days before it expires, and flag it if the issuing authority changes or the certificate is unexpectedly replaced.
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