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

TLS

vnpt.vn · 123.31.36.235:443

Unverified
Certificate verification failed. These are unverified certificate details presented by the server. SSL operation failed with code 1. OpenSSL Error messages: error:0A00018A:SSL routines::dh key too small

Certificate verification failed

Subject
C=VN ST=Ha Noi L=Ha Noi O=VIETNAM POSTS AND TELECOMMUNICATIONS GROUP CN=*.vnpt.vn
Issuer
C=BE O=GlobalSign nv-sa CN=GlobalSign GCC R46 OV TLS CA 2025
Valid from
2026-08-19T04:23:03+00:00
Expires
2027-03-06T04:23:03+00:00
Days remaining
122
Serial (hex)
135C1B35F80952379BD549DE
Signature
RSA-SHA256
Public key
RSA 2048

Subject alternative names (SAN)

DNS:*.vnpt.vn, DNS:www.vnpt.vn, DNS:owa.vnpt.vn, DNS:mail.vnpt.vn, DNS:autodiscover.vnpt.vn, DNS:vnpt.vn

SHA-256 fingerprint

EE:5C:0B:FF:BB:33:D3:C2:22:49:15:CD:CF:9D:FF:B4:69:FF:CD:2E:6F:87:E4:B8:E5:C9:A7:AC:E1:51:F2:E3
Certificate extensions & PEM
keyUsage
Digital Signature, Key Encipherment
basicConstraints
CA:FALSE
authorityInfoAccess
CA Issuers - URI:http://secure.globalsign.com/cacert/gsgccr46ovtlsca2025.crt OCSP - URI:http://ocsp.globalsign.com/gsgccr46ovtlsca2025
certificatePolicies
Policy: 2.23.140.1.2.2
crlDistributionPoints
Full Name: URI:http://crl.globalsign.com/gsgccr46ovtlsca2025.crl
subjectAltName
DNS:*.vnpt.vn, DNS:www.vnpt.vn, DNS:owa.vnpt.vn, DNS:mail.vnpt.vn, DNS:autodiscover.vnpt.vn, DNS:vnpt.vn
authorityKeyIdentifier
69:74:3E:AF:C3:5B:01:95:49:EE:14:41:5A:93:FA:B1:30:98:DA:A2
extendedKeyUsage
TLS Web Server Authentication
subjectKeyIdentifier
FB:6A:67:61:10:50:B3:21:AA:73:61:37:AA:6F:60:89:88:62:79:5C
ct_precert_scts
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 : Aug 19 04:23:12.203 2026 GMT Extensions: none Signature : ecdsa-with-SHA256 30:45:02:21:00:E5:3A:41:10:57:C9:D0:3C:B9:3A:68: 45:75:B0:C1:07:40:E9:78:E8:43:EC:A9:9D:06:4F:B7: C1:C9:51:28:98:02:20:5C:02:F0:32:68:92:AE:6C:10: 39:21:D0:02:FC:A1:EF:3B:33:68:94:9D:59:ED:A7:F4: 7A:87:DD:48:11:ED:3C Signed Certificate Timestamp: Version : v1 (0x0) Log ID : 4C:63:DC:98:E5:9C:1D:AB:88:F6:1E:8A:3D:DE:AE:8F: AB:44:A3:37:7B:5F:9B:94:C3:FB:A1:9C:FC:C1:BE:26 Timestamp : Aug 19 04:23:11.535 2026 GMT Extensions: none Signature : ecdsa-with-SHA256 30:46:02:21:00:FC:81:47:FD:06:FE:EE:BD:8D:7D:38: 99:5F:11:0F:22:A1:7C:5C:C7:C6:B0:C0:D8:DA:BC:69: 42:C9:A0:5D:B8:02:21:00:B5:33:6F:44:4C:7A:32:DD: B5:02:E1:7D:D8:D4:9B:0E:EF:20:B7:E6:50:11:07:A2: 6A:83:97:06:2E:D8:EB:61 Signed Certificate Timestamp: Version : v1 (0x0) Log ID : 60:4C:9A:AF:7A:7F:77:5F:01:D4:06:FC:92:0D:C8:99: EB:0B:1C:7D:F8:C9:52:1B:FA:FA:17:77:3B:97:8B:C9 Timestamp : Aug 19 04:23:12.007 2026 GMT Extensions: none Signature : ecdsa-with-SHA256 30:46:02:21:00:91:AE:22:57:F0:95:F5:E8:8B:27:D7: D3:0C:4B:B7:70:34:27:82:CB:C9:30:9A:89:72:7B:01: 1E:C8:12:12:5E:02:21:00:95:E9:93:F6:02:B8:1B:D0: 94:E2:39:3F:6B:EE:2D:D3:8E:FF:4A:04:B6:C9:ED:E4: D1:FE:8A:82:C6:F6:C6:58
-----BEGIN CERTIFICATE-----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-----END CERTIFICATE-----

Cipher: Unavailable · Checked 2026-11-03T13:44:06+00:00

Server-presented chain · 2 additional certificates

Chain certificate 1

Subject
C=BE O=GlobalSign nv-sa CN=GlobalSign GCC R46 OV TLS CA 2025
Issuer
C=BE O=GlobalSign nv-sa CN=GlobalSign Root R46
Valid from
2025-09-17T02:55:56+00:00
Expires
2029-06-23T00:00:00+00:00
Days remaining
962
Serial (hex)
84435890836F67394182CB9C9A5DC99F
Signature
RSA-SHA256
Public key
RSA 2048

Subject alternative names (SAN)

No SAN extension was presented.

SHA-256 fingerprint

D1:60:E2:DE:4E:56:CB:10:B6:6C:1C:B0:AD:CB:79:CF:93:C7:8D:CD:9D:B3:0C:20:18:22:02:62:C0:40:63:F9
Certificate extensions & PEM
keyUsage
Digital Signature, Certificate Sign, CRL Sign
extendedKeyUsage
TLS Web Server Authentication
basicConstraints
CA:TRUE, pathlen:0
subjectKeyIdentifier
69:74:3E:AF:C3:5B:01:95:49:EE:14:41:5A:93:FA:B1:30:98:DA:A2
authorityKeyIdentifier
03:5C:AB:73:81:87:A8:CC:B0:A6:D5:94:E2:36:96:49:FF:05:99:2C
authorityInfoAccess
OCSP - URI:http://ocsp.globalsign.com/rootr46 CA Issuers - URI:http://secure.globalsign.com/cacert/rootr46.crt
crlDistributionPoints
Full Name: URI:http://crl.globalsign.com/rootr46.crl
certificatePolicies
Policy: 2.23.140.1.2.2 Policy: 1.3.6.1.4.1.4146.10.1.2
-----BEGIN CERTIFICATE-----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-----END CERTIFICATE-----

Chain certificate 2

Subject
C=BE O=GlobalSign nv-sa CN=GlobalSign Root R46
Issuer
OU=GlobalSign Root CA - R3 O=GlobalSign CN=GlobalSign
Valid from
2019-11-20T00:00:00+00:00
Expires
2029-03-18T00:00:00+00:00
Days remaining
865
Serial (hex)
75A8BAD878F8AF305F72DD1C1140DF3A
Signature
RSA-SHA384
Public key
RSA 4096

Subject alternative names (SAN)

No SAN extension was presented.

SHA-256 fingerprint

A6:3C:13:98:B5:F8:DD:2D:43:2F:BE:4C:2C:19:14:2B:EA:6D:5D:02:21:FA:E7:94:71:8A:E7:59:7A:CC:A9:6D
Certificate extensions & PEM
keyUsage
Digital Signature, Certificate Sign, CRL Sign
basicConstraints
CA:TRUE
subjectKeyIdentifier
03:5C:AB:73:81:87:A8:CC:B0:A6:D5:94:E2:36:96:49:FF:05:99:2C
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-----

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

View certificate JSON

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