SSL/TLS Certificate Lookup
Check a domain's SSL/TLS certificate — who issued it, when it expires, and whether the chain is trusted
o-sung.co.kr
SSL/TLS Certificate
SSL/TLS Certificate for o-sung.co.kr
Valid- Issued by (CA)
- Sectigo Limited
- Subject
- www.o-sung.co.kr
- Valid from
- Dec 29, 2025
- Valid until
- Dec 31, 2026 (87 days remaining)
- Public key
- RSA 2048-bit
- Serial
- E91CD315157E3C61913E0D8F423AB2C2
- SHA-256 fingerprint
- E4:3F:BA:EF:C0:B8:AA:84:04:0F:45:B2:8A:CF:9B:DB:DB:14:A6:ED:35:45:AD:D5:19:3D:81:8E:21:C3:B2:D0
- 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 Sep 23, 2026.
Never get surprised by o-sung.co.kr's certificate expiring
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Uptime
We visit the site from multiple regions worldwide and email you within minutes if it goes down, with a per-region breakdown so a real outage stands out from a regional blip.
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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