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

mail.osir.com · 173.208.224.213:443

Verified

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

Subject
CN=mail.osir.com
Issuer
C=US O=Let's Encrypt CN=YR2
Valid from
2026-09-10T06:37:16+00:00
Expires
2026-12-09T06:37:15+00:00
Days remaining
43
Serial (hex)
054034DF8A7409AB4B49353A6EEEF988F7F1
Signature
RSA-SHA256
Public key
RSA 4096

Subject alternative names (SAN)

DNS:autoconfig.osir.com, DNS:autoconfig.zana.tech, DNS:autodiscover.osir.com, DNS:autodiscover.zana.tech, DNS:autodiscover.zenithdn.com, DNS:mail.osir.com

SHA-256 fingerprint

31:58:EE:93:03:6D:48:51:BA:65:BA:00:A8:5B:AE:A3:A5:CB:F8:AD:F0:1F:83:CF:B6:EC:F1:18:75:67:00:D6
Certificate extensions & PEM
keyUsage
Digital Signature, Key Encipherment
extendedKeyUsage
TLS Web Server Authentication
basicConstraints
CA:FALSE
subjectKeyIdentifier
14:9D:00:86:1F:F1:C0:98:32:AB:E5:48:9D:7E:C9:9B:C9:B3:F1:48
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.osir.com, DNS:autoconfig.zana.tech, DNS:autodiscover.osir.com, DNS:autodiscover.zana.tech, DNS:autodiscover.zenithdn.com, DNS:mail.osir.com
certificatePolicies
Policy: 2.23.140.1.2.1
crlDistributionPoints
Full Name: URI:http://yr2.c.lencr.org/114.crl
ct_precert_scts
Signed Certificate Timestamp: Version : v1 (0x0) Log ID : D8:09:55:3B:94:4F:7A:FF:C8:16:19:6F:94:4F:85:AB: B0:F8:FC:5E:87:55:26:0F:15:D1:2E:72:BB:45:4B:14 Timestamp : Sep 10 07:35:46.708 2026 GMT Extensions: none Signature : ecdsa-with-SHA256 30:44:02:20:61:6D:B8:A7:1C:16:17:41:4B:40:BD:A8: A2:C8:CE:53:5A:47:9E:47:24:0D:16:3A:6B:04:B0:3C: 85:00:BD:39:02:20:6C:D3:62:F1:08:0C:B3:B2:33:03: 5D:AF:68:3C:48:D9:FD:6D:F2:1E:77:F8:81:7E:E8:E8: 3D:9B:C0:6D:8F:DA Signed Certificate Timestamp: Version : v1 (0x0) Log ID : 1A:8B:9D:6B:0F:FE:BF:81:B4:79:39:C6:D2:31:0A:86: D6:D1:02:D4:F0:46:E2:18:2C:9D:E3:5F:5E:26:25:EF Timestamp : Sep 10 07:35:47.365 2026 GMT Extensions: 00:00:05:00:3E:D6:E3:AE Signature : ecdsa-with-SHA256 30:45:02:20:6D:21:0F:95:DC:42:A5:81:49:30:E0:9D: 2D:24:71:1D:FE:2A:8B:29:9A:B5:96:97:64:54:4E:28: 5F:80:3F:12:02:21:00:DD:2B:3E:BD:70:19:28:42:8D: A9:9C:92:7D:2E:38:F0:83:DB:24:C7:D0:B0:21:6F:D5: 7A:F4:63:79:DE:40:94
-----BEGIN CERTIFICATE-----
MIIGbDCCBVSgAwIBAgISBUA034p0CatLSTU6bu75iPfxMA0GCSqGSIb3DQEBCwUA
MDMxCzAJBgNVBAYTAlVTMRYwFAYDVQQKEw1MZXQncyBFbmNyeXB0MQwwCgYDVQQD
EwNZUjIwHhcNMjYwOTEwMDYzNzE2WhcNMjYxMjA5MDYzNzE1WjAYMRYwFAYDVQQD
Ew1tYWlsLm9zaXIuY29tMIICIjANBgkqhkiG9w0BAQEFAAOCAg8AMIICCgKCAgEA
qAQeNsgOg6LunxoKrTg5X0lr4VRpj+XxZzNxvk3Poxl9bh6hITo1PHD+xKKUKATu
HijmzAl7x2FmTTdN19yqS1KbFeA7abT/UdFGySAk25pow69O9L0XmUTuq1mILJ3q
lXqe3SmSxMoTr3SdZFBDTfVtaJPpk5UYX9h8rAwu3wllPGu75vd/WGdSmlU7hNHV
BFadoFCpUiBogBxiScmbqhNiA3Ukeb3q/4eOG+QAJk4vEuAh/YDy+HVMd/yePQGi
ZBiAVyWWtkzUaMsY1xiF/6owvkye7ilbYJAkz22KASJAtQZAXIS/vUL2JnmXV30+
iRYWY7/oQNODAmjDxYRbQR/plSO1slHc81T19jWb+EiYpsGdo6OD6jceYxj9v/7d
uPbNM34sNqpTIitrp+Y5wO+gqaDpTAU0c0bwh4ItORM4GudPgIzt6RajQ25I4YH5
pM52dY1uCUvb6Y61rrPOxmuxMFjXiEHDBtDdVW2GLPcj4vgFgt+96YnYUY4SaroG
5sKHqUfEQ/t5mGNPXEZuirdTForUUIPhy/KygNyjAQ03+9DyGNV3BgnY3dDfWKT4
ba82P3K+jjdwBP0NfkbrUUUXFk6vQBzuwcpbGU0YHI/8vkncnUnMSTQ+QpWd94gD
94HKKPfV769DhjButOi6mx7mvE1O74Mu0zEotk6hG+ECAwEAAaOCApMwggKPMA4G
A1UdDwEB/wQEAwIFoDATBgNVHSUEDDAKBggrBgEFBQcDATAMBgNVHRMBAf8EAjAA
MB0GA1UdDgQWBBQUnQCGH/HAmDKr5UidfsmbybPxSDAfBgNVHSMEGDAWgBRAFS0m
ee0yIJ7fmnId1jIfgQyBDDAzBggrBgEFBQcBAQQnMCUwIwYIKwYBBQUHMAKGF2h0
dHA6Ly95cjIuaS5sZW5jci5vcmcvMIGPBgNVHREEgYcwgYSCE2F1dG9jb25maWcu
b3Npci5jb22CFGF1dG9jb25maWcuemFuYS50ZWNoghVhdXRvZGlzY292ZXIub3Np
ci5jb22CFmF1dG9kaXNjb3Zlci56YW5hLnRlY2iCGWF1dG9kaXNjb3Zlci56ZW5p
dGhkbi5jb22CDW1haWwub3Npci5jb20wEwYDVR0gBAwwCjAIBgZngQwBAgEwLwYD
VR0fBCgwJjAkoCKgIIYeaHR0cDovL3lyMi5jLmxlbmNyLm9yZy8xMTQuY3JsMIIB
CwYKKwYBBAHWeQIEAgSB/ASB+QD3AHUA2AlVO5RPev/IFhlvlE+Fq7D4/F6HVSYP
FdEucrtFSxQAAAGgij5/FAAABAMARjBEAiBhbbinHBYXQUtAvaiiyM5TWkeeRyQN
FjprBLA8hQC9OQIgbNNi8QgMs7IzA12vaDxI2f1t8h53+IF+6Og9m8Btj9oAfgAa
i51rD/6/gbR5OcbSMQqG1tEC1PBG4hgsneNfXiYl7wAAAaCKPoGlAAgAAAUAPtbj
rgQDAEcwRQIgbSEPldxCpYFJMOCdLSRxHf4qiymatZaXZFROKF+APxICIQDdKz69
cBkoQo2pnJJ9Ljjwg9skx9CwIW/VevRjed5AlDANBgkqhkiG9w0BAQsFAAOCAQEA
MP3EhNJWw0VW6sEuE9Veq37B9GV2LEhGAZ/OyLd/CEl1PRMeHpV/zPMEN1V5hErM
0YRdSUS0YP+EWVtn46Wv8j/E3LosCP/Wm0qWzb6T4aOBQtCIPfWTvH6buKwhwp/6
OQWctaXndF5XNAz6wxN195qmX+YPfsd8OkKECUaiayJaQr8brEj7PnJ2IMrPkrub
OQStQQKPn+dYBAT5ZlCGwHjJA97+ll5/KgtfINW7GdX9TAEgecS9HybpZC2hjpAN
bZqWL2ZtmkUByGhlCu3zPWdkTUNy0xgZ21xPDXVvWNi8Tfa3g0Fbsp5UTFvPyLGO
xjhurn69ygREaEUl+ukb/A==
-----END CERTIFICATE-----

Cipher: TLS_AES_256_GCM_SHA384 · Checked 2026-10-26T11:54:37+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
677
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
2138
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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