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

TLSv1.2

mail.dcenter.pl · 213.5.8.30:443

Unverified

Certificate verification failed. These are unverified certificate details presented by the server. SSL operation failed with code 1. OpenSSL Error messages: error:0A000086:SSL routines::certificate verify failed

The certificate has expired.

Certificate verification failed

Subject: C=pl ST=Some-State O=dcenter.pl OU=noc@dcenter.pl CN=poczta.dcenter.pl emailAddress=noc@dcenter.pl
Issuer: C=pl ST=Some-State L=Warszawa O=dcenter.pl CN=dcenter.pl
Valid from: 2014-12-28T15:45:49+00:00
Expires: 2015-12-28T15:45:49+00:00
Days remaining: -3949
Serial (hex): 20130916
Signature: RSA-SHA1
Public key: RSA 4096

Subject alternative names (SAN)

No SAN extension was presented.

SHA-256 fingerprint

02:60:D6:B9:66:08:9A:77:80:B8:97:64:7C:AB:0E:F3:A3:20:5D:AC:2F:19:53:12:DA:E7:C2:E6:4D:08:B3:E5

Certificate extensions & PEM

basicConstraints: CA:FALSE
nsComment: OpenSSL Generated Certificate
subjectKeyIdentifier: 37:F1:B6:D6:12:A1:EC:20:64:17:EE:CD:39:37:EC:E2:10:72:EE:05
authorityKeyIdentifier: DirName:/C=pl/ST=Some-State/L=Warszawa/O=dcenter.pl/CN=dcenter.pl serial:FF:F1:B2:F8:2F:ED:6A:27

-----BEGIN CERTIFICATE-----
MIIGQDCCBCigAwIBAgIEIBMJFjANBgkqhkiG9w0BAQUFADBfMQswCQYDVQQGEwJw
bDETMBEGA1UECBMKU29tZS1TdGF0ZTERMA8GA1UEBxMIV2Fyc3phd2ExEzARBgNV
BAoTCmRjZW50ZXIucGwxEzARBgNVBAMTCmRjZW50ZXIucGwwHhcNMTQxMjI4MTU0
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ARYObm9jQGRjZW50ZXIucGwwggIiMA0GCSqGSIb3DQEBAQUAA4ICDwAwggIKAoIC
AQDd/sKK+qhgXK2ampC0ntHa1T6HndoRCtPCMdfF4uqnuHHHbo9O2fSlINqiBWOo
coNkT2pk98/CLANDcM95VvIZVaGHKJKVXGsx75hh25743uglN9Zp0k2B4b0+z87e
lsiAXlve+G+C1+gpFsQ65ykH8l8vRR/Gh+t5IwNMQPD6rGJNsIc0hKr14Sl9KKgQ
M0j1cdN5WlGstNoSPCEBilV9vtC9Jnmh+C0NchEHTDspG5TQOcNF9shefQ1Vrc+h
k+Gwwi8zOUQadbfJq3p1a/mFwshRTh4W3YodsJVGi1WV08RG0l5jX8cSiW/+HaoN
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gyA9KFizcOBFP1lBjQDSr90fwqH1Etwp8UPj27Sv6TwYyoa/o+j/2Eutu7lNwe1I
Nh2BLNExVwTYMIgFZKN05YYPxcOy7pJnjtvYUyFyyfAmO+QlOPspcWKpIOB0PvqB
siRg76TOL8CBV0O4YUBTKEw6yG3ApD5F3G/c8W2EnbiwPV6XWNuHEn08GIH5JPOJ
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A1UdEwQCMAAwLAYJYIZIAYb4QgENBB8WHU9wZW5TU0wgR2VuZXJhdGVkIENlcnRp
ZmljYXRlMB0GA1UdDgQWBBQ38bbWEqHsIGQX7s05N+ziEHLuBTB5BgNVHSMEcjBw
oWOkYTBfMQswCQYDVQQGEwJwbDETMBEGA1UECBMKU29tZS1TdGF0ZTERMA8GA1UE
BxMIV2Fyc3phd2ExEzARBgNVBAoTCmRjZW50ZXIucGwxEzARBgNVBAMTCmRjZW50
ZXIucGyCCQD/8bL4L+1qJzANBgkqhkiG9w0BAQUFAAOCAgEAGVlbdQhPsZ2jziYk
p5aF5kA2DPPM4hFpf1Wm95hDA07MVgt4MSI7SCn/UkqdHZX+A8fzrIZjl3LLduSf
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kHzktlQHZ15q2/ZYo6USRIZyrzRpkeUm174C+ch4eIlPKJALaotgMQKQLEM8vjO3
ek4kPRpG/kar4EqDM1b/fYJf8Hayn+l5x75kRFWAkdRP7jTRkfqwr0oqa2fKkRhs
j/jVDJhT8S9+08RVE3bQNrSDGEWf2+qOeY0JBoCgab8eSfjyqV/rkV7gW3c9+QSU
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B2zP0yeCei8NlLW84Co9vZJhfTcp8uT4Ypq/Pu1vh5Fb6aEPDPSCNXuT84OH6mKu
8kjuEpxNrRBe8Ncug1DYppn17ggNcfQGanTsYKX39oCj7QuBAJyeLKyAMSJNKSY9
C89v1LixfnQU6IrP8LqGiJ29H5yQMLp+AmhZG5OZjyh2Cr+a+7B1ffJEg9SCCB7N
LrsPEI/eksW5HqP/dNCXsVIC7dxwRJzNwMLD9pnUD+mUuerGBSeN9105MU/yzaje
C1JYh+l2lqL145le25hZmrdCUFQ=
-----END CERTIFICATE-----

Cipher: ECDHE-RSA-AES128-GCM-SHA256 · Checked 2026-10-20T02:49:04+00:00

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

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