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

263xmail.com · 211.150.66.111:443

Unverified
Certificate verification failed. These are unverified certificate details presented by the server. Peer certificate CN=`*.cast.org.cn' did not match expected CN=`263xmail.com'

Certificate verification failed

Subject
C=CN ST=北京市 L=北京市 O=中国科协信息中心 CN=*.cast.org.cn
Issuer
C=BE O=GlobalSign nv-sa CN=GlobalSign RSA OV SSL CA 2018
Valid from
2026-06-26T09:50:34+00:00
Expires
2027-01-11T09:50:34+00:00
Days remaining
106
Serial (hex)
7609CA0DDBCBD7EABFA7D03C
Signature
RSA-SHA256
Public key
RSA 2048

Subject alternative names (SAN)

DNS:*.cast.org.cn, DNS:cast.org.cn

SHA-256 fingerprint

61:D3:48:E5:B9:9D:04:19:7A:08:06:4B:3C:4C:ED:20:E8:BC:64:10:FD:17:F5:45:00:46:F2:85:CD:9E:52:50
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:*.cast.org.cn, DNS:cast.org.cn
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
2D:D4:29:3C:5D:8A:1C:65:47:8F:17:E3:4E:A2:66:F2:CD:5F:4F:EB
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 : Jun 26 09:50:37.286 2026 GMT Extensions: none Signature : ecdsa-with-SHA256 30:44:02:20:2C:E7:C8:86:28:1F:88:36:DC:2D:DE:1F: 02:D7:94:74:9A:4C:6C:BC:AC:E5:64:BB:F0:4D:91:DE: 3C:02:51:01:02:20:3C:16:66:B0:77:2F:34:82:12:C8: A2:80:AE:AA:AA:08:59:1B:59:0B:C7:F2:66:6C:62:AB: 89:08:98:3E:0E:BE 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 : Jun 26 09:50:37.139 2026 GMT Extensions: none Signature : ecdsa-with-SHA256 30:46:02:21:00:E7:40:FB:66:E9:02:C5:7C:FF:A6:2E: 0C:EE:99:8F:32:7B:61:44:35:34:EC:90:A0:B0:A8:67: 3D:C1:53:4F:C0:02:21:00:A4:E0:3A:70:2D:78:B4:EE: 2E:CC:0B:7C:C1:E3:E2:93:E6:BD:04:6E:39:3D:FD:D3: 85:82:79:C4:BE:8E:D5:6C 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 : Jun 26 09:50:37.095 2026 GMT Extensions: none Signature : ecdsa-with-SHA256 30:45:02:20:4C:97:68:A1:FA:CB:34:1C:3D:C1:14:9C: FE:4B:87:5D:60:1C:31:E3:46:CE:C0:BD:56:FC:DB:18: 7E:DA:EC:37:02:21:00:C4:64:3E:D1:97:93:02:DF:F5: 39:05:36:BF:F8:91:D9:3B:E7:87:9E:BC:11:E3:B5:C1: 75:8E:88:96:C3:CB:10
-----BEGIN CERTIFICATE-----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=
-----END CERTIFICATE-----

Cipher: TLS_AES_128_GCM_SHA256 · Checked 2026-09-26T17:01:23+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
786
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
C=BE O=GlobalSign nv-sa OU=Root CA CN=GlobalSign Root CA
Valid from
2018-09-19T00:00:00+00:00
Expires
2028-01-28T12:00:00+00:00
Days remaining
488
Serial (hex)
01EE5F169DFF97352B6465D66A
Signature
RSA-SHA256
Public key
RSA 2048

Subject alternative names (SAN)

No SAN extension was presented.

SHA-256 fingerprint

44:5E:EC:78:BC:61:21:50:44:A0:37:96:56:AA:2D:5D:B5:E4:2F:76:CB:70:B8:D1:4C:20:77:AA:94:3D:4E:BB
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
authorityKeyIdentifier
60:7B:66:1A:45:0D:97:CA:89:50:2F:7D:04:CD:34:A8:FF:FC:FD:4B
authorityInfoAccess
OCSP - URI:http://ocsp.globalsign.com/rootr1
crlDistributionPoints
Full Name: URI:http://crl.globalsign.com/root.crl
certificatePolicies
Policy: X509v3 Any Policy CPS: https://www.globalsign.com/repository/
-----BEGIN CERTIFICATE-----
MIIETjCCAzagAwIBAgINAe5fFp3/lzUrZGXWajANBgkqhkiG9w0BAQsFADBXMQsw
CQYDVQQGEwJCRTEZMBcGA1UEChMQR2xvYmFsU2lnbiBudi1zYTEQMA4GA1UECxMH
Um9vdCBDQTEbMBkGA1UEAxMSR2xvYmFsU2lnbiBSb290IENBMB4XDTE4MDkxOTAw
MDAwMFoXDTI4MDEyODEyMDAwMFowTDEgMB4GA1UECxMXR2xvYmFsU2lnbiBSb290
IENBIC0gUjMxEzARBgNVBAoTCkdsb2JhbFNpZ24xEzARBgNVBAMTCkdsb2JhbFNp
Z24wggEiMA0GCSqGSIb3DQEBAQUAA4IBDwAwggEKAoIBAQDMJXaQeQZ4Ihb1wIO2
hMoonv0FdhHFrYhy/EYCQ8eyip0EXyTLLkvhYIJG4VKrDIFHcGzdZNHr9SyjD4I9
DCuul9e2FIYQebs7E4B3jAjhSdJqYi8fXvqWaN+JJ5U4nwbXPsnLJlkNc96wyOkm
DoMVxu9bi9IEYMpJpij2aTv2y8gokeWdimFXN6x0FNx04Druci8unPvQu7/1PQDh
BjPogiuuU6Y6FnOM3UEOIDrAtKeh6bJPkC4yYOlXy7kEkmho5TgmYHWyn3f/kRTv
riBJ/K1AFUjRAjFhGV64l++td7dkmnq/X8ET75ti+w1s4FRpFqkD2m7pg5NxdsZp
hYIXAgMBAAGjggEiMIIBHjAOBgNVHQ8BAf8EBAMCAQYwDwYDVR0TAQH/BAUwAwEB
/zAdBgNVHQ4EFgQUj/BLf6guRSSuTVD6Y5qL3uLdG7wwHwYDVR0jBBgwFoAUYHtm
GkUNl8qJUC99BM00qP/8/UswPQYIKwYBBQUHAQEEMTAvMC0GCCsGAQUFBzABhiFo
dHRwOi8vb2NzcC5nbG9iYWxzaWduLmNvbS9yb290cjEwMwYDVR0fBCwwKjAooCag
JIYiaHR0cDovL2NybC5nbG9iYWxzaWduLmNvbS9yb290LmNybDBHBgNVHSAEQDA+
MDwGBFUdIAAwNDAyBggrBgEFBQcCARYmaHR0cHM6Ly93d3cuZ2xvYmFsc2lnbi5j
b20vcmVwb3NpdG9yeS8wDQYJKoZIhvcNAQELBQADggEBACNw6c/ivvVZrpRCb8RD
M6rNPzq5ZBfyYgZLSPFAiAYXof6r0V88xjPy847dHx0+zBpgmYILrMf8fpqHKqV9
D6ZX7qw7aoXW3r1AY/itpsiIsBL89kHfDwmXHjjqU5++BfQ+6tOfUBJ2vgmLwgtI
fR4uUfaNU9OrH0Abio7tfftPeVZwXwzTjhuzp3ANNyuXlava4BJrHEDOxcd+7cJi
WOx37XMiwor1hkOIreoTbv3Y/kIvuX1erRjvlJDKPSerJpSZdcfL03v3ykzTr1Eh
kluEfSufFT90y1HonoMOFm8b50bOI7355KKL0jlrqnkckSziYSQtjipIcJDEHsXo
4HA=
-----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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