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THE CERTIFICATE BEHIND THE CONNECTION

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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

sejongnetworks.com · 203.251.216.5:443

Verified

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

Subject
C=KR ST=Gyeonggi-do L=Gwacheon-si O=Sejong Telecom, Inc. CN=*.sejongnetworks.com
Issuer
C=BE O=GlobalSign nv-sa CN=GlobalSign RSA OV SSL CA 2018
Valid from
2026-04-08T05:36:09+00:00
Expires
2026-10-24T05:36:09+00:00
Days remaining
31
Serial (hex)
39231B7F3B3D9A10E23F1E6C
Signature
RSA-SHA256
Public key
RSA 2048

Subject alternative names (SAN)

DNS:*.sejongnetworks.com, DNS:sejongnetworks.com

SHA-256 fingerprint

1A:B5:6A:6F:36:19:91:7A:07:76:18:73:EA:3E:0E:42:32:78:72:EF:68:3F:FE:97:91:91:79:D2:85:CD:97:5D
Certificate extensions & PEM
keyUsage
Digital Signature, Key Encipherment
basicConstraints
CA:FALSE
authorityInfoAccess
CA Issuers - URI:http://secure.globalsign.com/cacert/gsrsaovsslca2018.crt OCSP - URI:http://ocsp.globalsign.com/gsrsaovsslca2018
certificatePolicies
Policy: 1.3.6.1.4.1.4146.1.20 CPS: https://www.globalsign.com/repository/ Policy: 2.23.140.1.2.2
subjectAltName
DNS:*.sejongnetworks.com, DNS:sejongnetworks.com
extendedKeyUsage
TLS Web Server Authentication, TLS Web Client Authentication
authorityKeyIdentifier
F8:EF:7F:F2:CD:78:67:A8:DE:6F:8F:24:8D:88:F1:87:03:02:B3:EB
subjectKeyIdentifier
95:6F:6B:FD:4B:52:7B:44:50:94:1A:6B:2B:35:7B:5E:7C:07:48:D0
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 : Apr 8 05:36:12.261 2026 GMT Extensions: none Signature : ecdsa-with-SHA256 30:45:02:21:00:F1:32:77:B3:D9:BF:7A:46:58:53:B9: 2C:40:DB:C4:A9:A3:2B:29:F4:A1:FD:D4:A0:56:52:94: 1E:96:E2:86:49:02:20:04:D0:7E:98:E7:F4:0B:04:F0: 45:C6:85:74:F3:2C:F9:4A:13:E7:4F:74:BE:AC:8A:54: 27:35:B6:D3:DA:32:E3 Signed Certificate Timestamp: Version : v1 (0x0) Log ID : CB:38:F7:15:89:7C:84:A1:44:5F:5B:C1:DD:FB:C9:6E: F2:9A:59:CD:47:0A:69:05:85:B0:CB:14:C3:14:58:E7 Timestamp : Apr 8 05:36:12.264 2026 GMT Extensions: none Signature : ecdsa-with-SHA256 30:44:02:20:71:ED:17:54:85:BE:62:1F:2A:1A:85:23: 8E:20:92:FF:4C:A3:DF:67:0A:17:22:00:E7:78:FE:A9: 6D:B0:7C:7B:02:20:62:2C:B6:97:31:6B:1E:28:1F:0F: 60:86:66:CE:EE:78:5B:D1:69:C7:CE:0B:67:A9:5C:11: 6F:BC:D1:CE:F2:61 Signed Certificate Timestamp: Version : v1 (0x0) Log ID : C2:31:7E:57:45:19:A3:45:EE:7F:38:DE:B2:90:41:EB: C7:C2:21:5A:22:BF:7F:D5:B5:AD:76:9A:D9:0E:52:CD Timestamp : Apr 8 05:36:12.251 2026 GMT Extensions: none Signature : ecdsa-with-SHA256 30:46:02:21:00:A5:F3:11:CF:77:23:C0:CB:AF:60:1E: ED:81:59:9A:7F:81:32:1E:43:D7:9A:CA:93:CF:73:46: 85:66:1C:4C:66:02:21:00:86:71:42:16:7E:A5:08:0F: FB:C8:E1:14:E5:C3:3E:E6:7F:72:D1:F0:43:9B:08:56: 91:9C:BA:64:1B:0A:4D:35
-----BEGIN CERTIFICATE-----
MIIGcDCCBVigAwIBAgIMOSMbfzs9mhDiPx5sMA0GCSqGSIb3DQEBCwUAMFAxCzAJ
BgNVBAYTAkJFMRkwFwYDVQQKExBHbG9iYWxTaWduIG52LXNhMSYwJAYDVQQDEx1H
bG9iYWxTaWduIFJTQSBPViBTU0wgQ0EgMjAxODAeFw0yNjA0MDgwNTM2MDlaFw0y
NjEwMjQwNTM2MDlaMHcxCzAJBgNVBAYTAktSMRQwEgYDVQQIEwtHeWVvbmdnaS1k
bzEUMBIGA1UEBxMLR3dhY2hlb24tc2kxHTAbBgNVBAoTFFNlam9uZyBUZWxlY29t
LCBJbmMuMR0wGwYDVQQDDBQqLnNlam9uZ25ldHdvcmtzLmNvbTCCASIwDQYJKoZI
hvcNAQEBBQADggEPADCCAQoCggEBAJsh9bgnUVRJ+QhOME5ZSK0vK2jGYATrREqA
J0Ie6aYAX7R7rzS4WWr0EBgLaL7gRKJ5uGRPQtS+KgWeBGDBijomq+FfEqyGBRAk
/aJ3da8r+RNkDJLr9+IVlM7v3btDJKz5I/F7pULGvYQQX1E3t85ul8Q66ILxzCg/
830fsM8kJvyH6Uv2c1Jvlu5Ynfo7PqOIxN03KF2wBmhvU/xo1k/2A+PAluO+pdZk
XJGd+C0UZYTh+PA6wIH8BgPvLaiEu1IwXjfJmHs7EKf4h0HFCKRA21eIBg+QzPL6
kZfQxzAYFPhPnk5ZA+bT3WKBUy/MOQaKkj8Wzx+8HmSRB4jM70MCAwEAAaOCAyEw
ggMdMA4GA1UdDwEB/wQEAwIFoDAMBgNVHRMBAf8EAjAAMIGOBggrBgEFBQcBAQSB
gTB/MEQGCCsGAQUFBzAChjhodHRwOi8vc2VjdXJlLmdsb2JhbHNpZ24uY29tL2Nh
Y2VydC9nc3JzYW92c3NsY2EyMDE4LmNydDA3BggrBgEFBQcwAYYraHR0cDovL29j
c3AuZ2xvYmFsc2lnbi5jb20vZ3Nyc2FvdnNzbGNhMjAxODBWBgNVHSAETzBNMEEG
CSsGAQQBoDIBFDA0MDIGCCsGAQUFBwIBFiZodHRwczovL3d3dy5nbG9iYWxzaWdu
LmNvbS9yZXBvc2l0b3J5LzAIBgZngQwBAgIwMwYDVR0RBCwwKoIUKi5zZWpvbmdu
ZXR3b3Jrcy5jb22CEnNlam9uZ25ldHdvcmtzLmNvbTAdBgNVHSUEFjAUBggrBgEF
BQcDAQYIKwYBBQUHAwIwHwYDVR0jBBgwFoAU+O9/8s14Z6jeb48kjYjxhwMCs+sw
HQYDVR0OBBYEFJVva/1LUntEUJQaays1e158B0jQMIIBfgYKKwYBBAHWeQIEAgSC
AW4EggFqAWgAdgCUTkOH+uzB74HzGSQmqBhlAcfTXzgCAT9yZ31VNy4Z2AAAAZ1r
l1HlAAAEAwBHMEUCIQDxMnez2b96RlhTuSxA28Spoysp9KH91KBWUpQeluKGSQIg
BNB+mOf0CwTwRcaFdPMs+UoT5090vqyKVCc1ttPaMuMAdQDLOPcViXyEoURfW8Hd
+8lu8ppZzUcKaQWFsMsUwxRY5wAAAZ1rl1HoAAAEAwBGMEQCIHHtF1SFvmIfKhqF
I44gkv9Mo99nChciAOd4/qltsHx7AiBiLLaXMWseKB8PYIZmzu54W9Fpx84LZ6lc
EW+80c7yYQB3AMIxfldFGaNF7n843rKQQevHwiFaIr9/1bWtdprZDlLNAAABnWuX
UdsAAAQDAEgwRgIhAKXzEc93I8DLr2Ae7YFZmn+BMh5D15rKk89zRoVmHExmAiEA
hnFCFn6lCA/7yOEU5cM+5n9y0fBDmwhWkZy6ZBsKTTUwDQYJKoZIhvcNAQELBQAD
ggEBABpJiJMN/iSWvq0Wz88Od4Zz4FKprsbB4JqEAGPI9u0g2rKOJ0m1OA91YMvL
qhsLYVpoVpQ/cKw0hY2ZP5ihTmTRNzKGyXf5vw+/ufnubfU3L2fsN046etFmmIhk
+nHOaEq1Kv/gnYMFkkoZNBPPoxp6B/Rtj9njE+UGg/YUIJkCKnpUpcMDvPmKK714
WZ62+hOBvTlJn2+fLEEEUOCoaAXpyvvT8n9jW064MB4AXwijioN+THnC3YOXVLxd
dg5w0djAn0pg+mcs31yPLHOLRVF9JhhP6Bj7AG55vSK5D7WV9HhCDjQZk6HpZzu5
Pup/HSnke0MGRpU1DzOxtPYMNGs=
-----END CERTIFICATE-----

Cipher: TLS_AES_128_GCM_SHA256 · Checked 2026-09-22T16:14:13+00:00

Server-presented chain · 2 additional certificates

Chain certificate 1

Subject
C=BE O=GlobalSign nv-sa CN=GlobalSign RSA OV SSL CA 2018
Issuer
OU=GlobalSign Root CA - R3 O=GlobalSign CN=GlobalSign
Valid from
2018-11-21T00:00:00+00:00
Expires
2028-11-21T00:00:00+00:00
Days remaining
790
Serial (hex)
01EE5F221DFC623BD4333A8557
Signature
RSA-SHA256
Public key
RSA 2048

Subject alternative names (SAN)

No SAN extension was presented.

SHA-256 fingerprint

B6:76:FF:A3:17:9E:88:12:09:3A:1B:5E:AF:EE:87:6A:E7:A6:AA:F2:31:07:8D:AD:1B:FB:21:CD:28:93:76:4A
Certificate extensions & PEM
keyUsage
Digital Signature, Certificate Sign, CRL Sign
basicConstraints
CA:TRUE, pathlen:0
subjectKeyIdentifier
F8:EF:7F:F2:CD:78:67:A8:DE:6F:8F:24:8D:88:F1:87:03:02:B3:EB
authorityKeyIdentifier
8F:F0:4B:7F:A8:2E:45:24:AE:4D:50:FA:63:9A:8B:DE:E2:DD:1B:BC
authorityInfoAccess
OCSP - URI:http://ocsp2.globalsign.com/rootr3
crlDistributionPoints
Full Name: URI:http://crl.globalsign.com/root-r3.crl
certificatePolicies
Policy: X509v3 Any Policy CPS: https://www.globalsign.com/repository/
-----BEGIN CERTIFICATE-----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-----END CERTIFICATE-----

Chain certificate 2

Subject
OU=GlobalSign Root CA - R3 O=GlobalSign CN=GlobalSign
Issuer
OU=GlobalSign Root CA - R3 O=GlobalSign CN=GlobalSign
Valid from
2009-03-18T10:00:00+00:00
Expires
2029-03-18T10:00:00+00:00
Days remaining
907
Serial (hex)
04000000000121585308A2
Signature
RSA-SHA256
Public key
RSA 2048

Subject alternative names (SAN)

No SAN extension was presented.

SHA-256 fingerprint

CB:B5:22:D7:B7:F1:27:AD:6A:01:13:86:5B:DF:1C:D4:10:2E:7D:07:59:AF:63:5A:7C:F4:72:0D:C9:63:C5:3B
Certificate extensions & PEM
keyUsage
Certificate Sign, CRL Sign
basicConstraints
CA:TRUE
subjectKeyIdentifier
8F:F0:4B:7F:A8:2E:45:24:AE:4D:50:FA:63:9A:8B:DE:E2:DD:1B:BC
-----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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