DNS
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.zummer.su · 178.216.153.115:443

Unverified
Certificate verification failed. These are unverified certificate details presented by the server. SSL operation failed with code 1. OpenSSL Error messages: error:0A000086:SSL routines::certificate verify failed

Certificate verification failed

Subject
CN=mail.zummer.su
Issuer
C=US O=Let's Encrypt CN=YR2
Valid from
2026-08-05T06:27:12+00:00
Expires
2026-11-03T06:27:11+00:00
Days remaining
37
Serial (hex)
068CB94C4C56535D1345EE03B4481236D6D3
Signature
RSA-SHA256
Public key
RSA 2048

Subject alternative names (SAN)

DNS:mail.zummer.su

SHA-256 fingerprint

76:52:DE:18:2E:07:EE:E7:F6:E5:00:89:68:2D:44:80:AA:90:1F:72:1D:C2:D2:59:93:80:57:E9:9C:21:D7:B2
Certificate extensions & PEM
keyUsage
Digital Signature, Key Encipherment
extendedKeyUsage
TLS Web Server Authentication
basicConstraints
CA:FALSE
subjectKeyIdentifier
B5:FD:82:6C:E1:6C:A6:D4:8C:A3:68:0E:84:FF:2E:7D:36:90:15:3B
authorityKeyIdentifier
40:15:2D:26:79:ED:32:20:9E:DF:9A:72:1D:D6:32:1F:81:0C:81:0C
authorityInfoAccess
CA Issuers - URI:http://yr2.i.lencr.org/
subjectAltName
DNS:mail.zummer.su
certificatePolicies
Policy: 2.23.140.1.2.1
crlDistributionPoints
Full Name: URI:http://yr2.c.lencr.org/84.crl
ct_precert_scts
Signed Certificate Timestamp: Version : v1 (0x0) Log ID : 94:4E:43:87:FA:EC:C1:EF:81:F3:19:24:26:A8:18:65: 01:C7:D3:5F:38:02:01:3F:72:67:7D:55:37:2E:19:D8 Timestamp : Aug 5 07:25:42.277 2026 GMT Extensions: none Signature : ecdsa-with-SHA256 30:45:02:21:00:E7:FE:53:C7:34:96:89:CE:3E:21:95: A8:55:B6:01:F5:D0:DF:86:4C:3C:DE:FA:9C:29:90:71: 8B:1B:39:81:47:02:20:7F:D9:20:63:44:9E:65:B3:8C: 56:D7:66:E2:77:D6:5B:51:BD:8D:4F:EF:95:6C:AA:13: D3:9D:5A:69:23:11:6E Signed Certificate Timestamp: Version : v1 (0x0) Log ID : 26:E3:64:6E:58:69:21:23:BC:34:3F:47:24:35:9B:37: 92:CD:24:5A:88:D8:15:D3:93:33:FD:99:18:AB:47:23 Timestamp : Aug 5 07:25:41.123 2026 GMT Extensions: 00:00:05:00:31:6C:F4:0B Signature : ecdsa-with-SHA256 30:45:02:21:00:FA:89:DE:AD:59:1E:79:38:64:31:03: 9B:8B:93:24:CB:67:D6:3C:C3:0C:F0:9C:02:C4:94:E5: 03:AE:1C:7C:A5:02:20:21:44:5B:16:A5:8E:C8:98:10: 0F:8A:44:1B:78:63:4A:D4:60:74:16:1E:A7:FB:CA:D8: 4F:89:99:22:64:C7:1C
-----BEGIN CERTIFICATE-----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-----END CERTIFICATE-----

Cipher: ECDHE-RSA-AES256-GCM-SHA384 · Checked 2026-09-27T04:35:53+00:00

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

View certificate JSON

Registration / WHOIS →DNS records →