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THE CERTIFICATE BEHIND THE CONNECTION

TLS certificate checker.

Inspect SSL/TLS certificates for any public domain or subdomain.

Checks HTTPS on port 443, including subject alternative names, validity dates and the presented chain.

SSL certificate

TLSv1.2

mail.sepanta.net · 85.133.129.194:443

Unverified
Certificate verification failed. These are unverified certificate details presented by the server. Peer certificate subjectAltName did not match expected name `mail.sepanta.net'

Certificate verification failed

Subject
CN=*.sepanta.com
Issuer
C=PL O=Asseco Data Systems S.A. CN=Certum DV TLS G2 R39 CA
Valid from
2026-06-27T08:29:26+00:00
Expires
2027-01-12T08:29:25+00:00
Days remaining
85
Serial (hex)
27E6D931B9E85E26F3C93B599D6CBA1B
Signature
RSA-SHA256
Public key
RSA 4096

Subject alternative names (SAN)

DNS:*.sepanta.com, DNS:sepanta.com

SHA-256 fingerprint

8C:44:78:8E:DB:DE:5B:A0:71:CE:4F:75:5F:44:E1:91:FB:02:2E:AD:20:93:83:0C:99:39:C2:9E:8A:22:66:7B
Certificate extensions & PEM
basicConstraints
CA:FALSE
crlDistributionPoints
Full Name: URI:http://certumdvtlsg2r39ca.crl.certum.pl/certumdvtlsg2r39ca.crl
authorityInfoAccess
OCSP - URI:http://certumdvtlsg2r39ca.ocsp-certum.com CA Issuers - URI:http://certumdvtlsg2r39ca.repository.certum.pl/certumdvtlsg2r39ca.cer
authorityKeyIdentifier
33:A8:77:B7:01:38:6F:5F:1F:24:24:A2:1E:6C:14:E3:6E:22:03:DF
certificatePolicies
Policy: 2.23.140.1.2.1 Policy: 1.2.616.1.113527.2.101.1
extendedKeyUsage
TLS Web Server Authentication, TLS Web Client Authentication
keyUsage
Digital Signature, Key Encipherment
subjectAltName
DNS:*.sepanta.com, DNS:sepanta.com
ct_precert_scts
Signed Certificate Timestamp: Version : v1 (0x0) Log ID : 44:C2:BD:0C:E9:14:0E:64:A5:C9:4A:01:93:0A:5A:A1: BB:35:97:0E:00:EE:11:16:89:68:2A:1C:44:D7:B5:66 Timestamp : Jun 27 08:29:27.459 2026 GMT Extensions: none Signature : ecdsa-with-SHA256 30:44:02:20:4F:DC:2B:9D:74:55:14:44:1A:51:7C:FC: C6:8C:96:E9:35:8A:59:A3:79:A3:BB:6D:98:C6:07:1B: E3:30:D7:D4:02:20:10:E1:FD:3E:39:A0:20:F5:6C:0A: 13:84:03:EF:FC:4F:DA:CE:BE:33:25:83:21:51:0E:90: 50:BD:0F:11:E9:77 Signed Certificate Timestamp: Version : v1 (0x0) Log ID : 1C:9F:68:2C:E9:FA:F0:45:69:50:F8:1B:96:8A:87:DD: DB:32:10:D8:4C:E6:C8:B2:E3:82:52:4A:C4:CF:59:9F Timestamp : Jun 27 08:29:27.656 2026 GMT Extensions: none Signature : ecdsa-with-SHA256 30:46:02:21:00:EB:81:A3:42:70:1A:89:24:AD:AB:59: 21:C8:29:1C:03:41:02:5E:50:30:F0:B3:4E:5D:C4:40: F8:AA:A6:39:45:02:21:00:C3:01:7E:B6:25:9B:D5:39: 84:AD:88:C9:16:01:A9:E8:1A:53:35:48:35:80:9A:57: 12:6C:1C:B0:B7:52:EC:9F Signed Certificate Timestamp: Version : v1 (0x0) Log ID : D6:D5:8D:A9:D0:17:53:F3:6A:4A:A0:C7:57:49:02:AF: EB:C7:DC:2C:D3:8C:D9:F7:64:C8:0C:89:19:1E:9F:02 Timestamp : Jun 27 08:29:27.410 2026 GMT Extensions: none Signature : ecdsa-with-SHA256 30:46:02:21:00:D9:38:D2:69:01:77:04:4F:70:E4:88: 59:C4:86:60:86:B0:E8:87:0C:E2:F2:7C:5C:90:8A:77: 8A:3D:DF:7D:9C:02:21:00:E5:86:90:87:14:B5:E3:9C: 1E:29:38:60:FB:BF:CE:D1:E4:60:93:D1:9A:F3:EB:AA: 73:2B:D5:F8:97:9C:9B:AB
-----BEGIN CERTIFICATE-----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KACvi4ZMvtVAmkDOWwIDAQABo4IDHTCCAxkwDAYDVR0TAQH/BAIwADBPBgNVHR8E
SDBGMESgQqBAhj5odHRwOi8vY2VydHVtZHZ0bHNnMnIzOWNhLmNybC5jZXJ0dW0u
cGwvY2VydHVtZHZ0bHNnMnIzOWNhLmNybDCBmgYIKwYBBQUHAQEEgY0wgYowNQYI
KwYBBQUHMAGGKWh0dHA6Ly9jZXJ0dW1kdnRsc2cycjM5Y2Eub2NzcC1jZXJ0dW0u
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FoAUM6h3twE4b18fJCSiHmwU424iA98wIQYDVR0gBBowGDAIBgZngQwBAgEwDAYK
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MIIBfwYKKwYBBAHWeQIEAgSCAW8EggFrAWkAdQBEwr0M6RQOZKXJSgGTClqhuzWX
DgDuERaJaCocRNe1ZgAAAZ8IMrAjAAAEAwBGMEQCIE/cK510VRREGlF8/MaMluk1
ilmjeaO7bZjGBxvjMNfUAiAQ4f0+OaAg9WwKE4QD7/xP2s6+MyWDIVEOkFC9DxHp
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AEgwRgIhAOuBo0JwGokkratZIcgpHANBAl5QMPCzTl3EQPiqpjlFAiEAwwF+tiWb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-----END CERTIFICATE-----

Cipher: ECDHE-RSA-AES256-GCM-SHA384 · Checked 2026-10-18T20:42:37+00:00

Server-presented chain · 1 additional certificate

Chain certificate 1

Subject
C=PL O=Asseco Data Systems S.A. CN=Certum DV TLS G2 R39 CA
Issuer
C=PL O=Asseco Data Systems S.A. OU=Certum Certification Authority CN=Certum Trusted Root CA
Valid from
2024-06-18T07:41:22+00:00
Expires
2039-06-05T07:41:22+00:00
Days remaining
4612
Serial (hex)
A82DD9E5DCAFDF13205E70043E6B95A8
Signature
RSA-SHA512
Public key
RSA 4096

Subject alternative names (SAN)

No SAN extension was presented.

SHA-256 fingerprint

83:C0:A5:A7:68:44:C8:40:DF:AF:82:0F:FD:02:AD:F6:57:3A:26:82:3E:F6:AF:75:8A:33:84:A0:AC:04:40:83
Certificate extensions & PEM
authorityInfoAccess
CA Issuers - URI:http://subca.repository.certum.pl/ctrca.cer OCSP - URI:http://subca.ocsp-certum.com
authorityKeyIdentifier
8C:FB:1C:75:BC:02:D3:9F:4E:2E:48:D9:F9:60:54:AA:C4:B3:4F:FA
basicConstraints
CA:TRUE, pathlen:0
crlDistributionPoints
Full Name: URI:http://subca.crl.certum.pl/ctrca.crl
extendedKeyUsage
TLS Web Client Authentication, TLS Web Server Authentication
keyUsage
Certificate Sign, CRL Sign
certificatePolicies
Policy: X509v3 Any Policy
subjectKeyIdentifier
33:A8:77:B7:01:38:6F:5F:1F:24:24:A2:1E:6C:14:E3:6E:22:03:DF
-----BEGIN CERTIFICATE-----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-----END CERTIFICATE-----

One endpoint on port 443. Server-presented chain; no revocation, OCSP, CT or full TLS security scan.

View certificate JSON

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