SSL/TLS Certificate Lookup

Check a domain's SSL/TLS certificate — who issued it, when it expires, and whether the chain is trusted

mas.com.pl

SSL/TLS Certificate

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SSL/TLS Certificate for mas.com.pl

Hostname mismatch

Issued by (CA): Sectigo Limited
Subject: *.usermd.net
Valid from: Jan 15, 2026
Valid until: Feb 14, 2027 (209 days remaining)
Public key: RSA 2048-bit
Serial: FEC4B8963BC129E545BDF2388099AB52
SHA-256 fingerprint: 1B:3C:E9:8D:39:C4:CC:0D:2E:5B:70:E9:63:68:36:42:39:02:B0:C2:AD:27:B0:8F:BC:2D:75:CD:C1:25:F0:94
Chain: Sectigo Public Server Authentication CA DV R36 → Sectigo Public Server Authentication Root R46 → USERTrust RSA Certification Authority

Subject Alternative Names (2)

*.usermd.net, usermd.net

Certificate Authority Authorization (CAA)

The serving CA (Sectigo Limited) is not among the authorities this domain's CAA records authorize (certum.pl, letsencrypt.org). This can indicate a misconfiguration or an unexpected issuance.