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

TLSv1.3

posta.xtsystem.it · 213.152.204.104:443

Verified

Certificate chain, hostname and dates verified using this server’s CA store.

Subject
CN=posta.xtsystem.it
Issuer
C=US O=Let's Encrypt CN=YR2
Valid from
2026-09-08T14:43:25+00:00
Expires
2026-12-07T14:43:24+00:00
Days remaining
55
Serial (hex)
069251E356DADFF968134BBB9B82E1203838
Signature
RSA-SHA256
Public key
RSA 4096

Subject alternative names (SAN)

DNS:autoconfig.mailcow.hppw.it, DNS:autoconfig.pensareweb.it, DNS:autoconfig.xtsystem.it, DNS:autodiscover.mailcow.hppw.it, DNS:autodiscover.pensareweb.it, DNS:autodiscover.xtsystem.it, DNS:posta.xtsystem.it

SHA-256 fingerprint

FF:D1:11:AA:9E:71:77:15:42:ED:6A:69:A9:E8:7F:3F:B0:77:4E:D1:35:3D:45:86:36:A4:22:CD:9C:58:65:14
Certificate extensions & PEM
keyUsage
Digital Signature, Key Encipherment
extendedKeyUsage
TLS Web Server Authentication
basicConstraints
CA:FALSE
subjectKeyIdentifier
45:E2:5C:5F:26:73:D0:34:D5:93:E7:17:19:BC:7E:56:95:19:01:7D
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:autoconfig.mailcow.hppw.it, DNS:autoconfig.pensareweb.it, DNS:autoconfig.xtsystem.it, DNS:autodiscover.mailcow.hppw.it, DNS:autodiscover.pensareweb.it, DNS:autodiscover.xtsystem.it, DNS:posta.xtsystem.it
certificatePolicies
Policy: 2.23.140.1.2.1
crlDistributionPoints
Full Name: URI:http://yr2.c.lencr.org/57.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 : Sep 8 15:41:55.442 2026 GMT Extensions: none Signature : ecdsa-with-SHA256 30:44:02:20:78:BE:CA:4B:26:F9:FF:F4:6B:4B:6E:16: 2E:99:66:FF:28:58:BB:5A:1C:42:31:D2:18:5E:B7:9A: FE:59:EB:4A:02:20:02:DA:83:79:66:BF:7E:06:59:38: F5:49:4F:75:C5:C0:EF:86:1A:41:1F:23:04:A2:C4:1F: 86:64:18:00:1B:C4 Signed Certificate Timestamp: Version : v1 (0x0) Log ID : 46:AF:86:3D:3B:3E:E5:9F:A5:77:DE:A8:24:5D:36:B0: D9:ED:22:A2:23:F4:61:77:41:22:94:52:EE:95:50:5F Timestamp : Sep 8 15:41:55.552 2026 GMT Extensions: 00:00:05:00:28:5A:FE:11 Signature : ecdsa-with-SHA256 30:44:02:20:46:F1:F2:98:76:D3:B8:35:E1:F0:33:55: DE:A7:9F:45:97:8A:76:3E:54:4F:2F:05:52:E3:B0:54: 23:54:E2:16:02:20:16:93:C4:4C:B2:C2:11:A3:BE:0C: 37:61:CB:A0:06:20:22:FD:B7:03:5A:E5:99:F7:68:93: DD:FD:03:C6:FF:92
-----BEGIN CERTIFICATE-----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-----END CERTIFICATE-----

Cipher: TLS_AES_256_GCM_SHA384 · Checked 2026-10-12T18:40:12+00:00

Server-presented chain · 2 additional certificates

Chain certificate 1

Subject
C=US O=Let's Encrypt CN=YR2
Issuer
C=US O=ISRG CN=Root YR
Valid from
2025-09-03T00:00:00+00:00
Expires
2028-09-02T23:59:59+00:00
Days remaining
691
Serial (hex)
4EBD24947E24D394802D84A52FD5B319
Signature
RSA-SHA256
Public key
RSA 2048

Subject alternative names (SAN)

No SAN extension was presented.

SHA-256 fingerprint

23:8B:85:A0:09:9C:65:B9:70:47:7D:57:24:F1:A1:D4:75:CE:50:58:CF:FE:4E:FA:87:33:89:9B:DB:86:3C:47
Certificate extensions & PEM
keyUsage
Digital Signature, Certificate Sign, CRL Sign
extendedKeyUsage
TLS Web Server Authentication
basicConstraints
CA:TRUE, pathlen:0
subjectKeyIdentifier
40:15:2D:26:79:ED:32:20:9E:DF:9A:72:1D:D6:32:1F:81:0C:81:0C
authorityKeyIdentifier
DE:E7:5B:60:D0:22:6D:40:28:7D:3F:0D:01:FE:A4:B5:52:B4:51:94
authorityInfoAccess
CA Issuers - URI:http://yr.i.lencr.org/
certificatePolicies
Policy: 2.23.140.1.2.1
crlDistributionPoints
Full Name: URI:http://yr.c.lencr.org/ 
-----BEGIN CERTIFICATE-----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==
-----END CERTIFICATE-----

Chain certificate 2

Subject
C=US O=ISRG CN=Root YR
Issuer
C=US O=Internet Security Research Group CN=ISRG Root X1
Valid from
2026-05-13T00:00:00+00:00
Expires
2032-09-02T23:59:59+00:00
Days remaining
2152
Serial (hex)
F24B6D17F9D9AD7CB1C9FEA78782699F
Signature
RSA-SHA256
Public key
RSA 4096

Subject alternative names (SAN)

No SAN extension was presented.

SHA-256 fingerprint

07:26:39:D0:B1:40:D5:BF:FA:E1:6A:D9:C3:F6:CC:60:86:04:06:21:F5:1E:E6:1A:6D:46:A8:91:5C:07:CF:76
Certificate extensions & PEM
keyUsage
Certificate Sign, CRL Sign
extendedKeyUsage
TLS Web Server Authentication
basicConstraints
CA:TRUE
subjectKeyIdentifier
DE:E7:5B:60:D0:22:6D:40:28:7D:3F:0D:01:FE:A4:B5:52:B4:51:94
authorityKeyIdentifier
79:B4:59:E6:7B:B6:E5:E4:01:73:80:08:88:C8:1A:58:F6:E9:9B:6E
authorityInfoAccess
CA Issuers - URI:http://x1.i.lencr.org/
certificatePolicies
Policy: 2.23.140.1.2.1
crlDistributionPoints
Full Name: URI:http://x1.c.lencr.org/ 
-----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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