bel.fi

Issued by Let's Encrypt Authority X3

About this certificate

This digital certificate with serial number 03:9e:4b:d5:65:35:98:05:63:fb:4e:98:1a:33:80:83:83:2e was issued on by Let's Encrypt.

With 4 subject alternative names this certificate can be used to secure multiple fqdn's. This certificate has already expired and will cause a warning or error message in the browser it's still listed on this site to allow you to look back on previously issued certificates. If we have found any compliance issues with this certificate they will be shown below. I hope this certificate review is providing you the detailed information in a simple form you where looking for.


We have idenified some issues with this certificate:
  • Subscriber Certificate: commonName is deprecated. (BRs: 7.1.4.2.2)

Certificate Subject

CN=bel.fi

Let's Encrypt

Organization: Let's Encrypt
Country: US

This certificate has expire since

Certificate Details

Serial Number (hex): 03:9e:4b:d5:65:35:98:05:63:fb:4e:98:1a:33:80:83:83:2e
Serial Number (int): 315202271880473264596184292113714656805678
Serial Number lenght: 138 bits, 18 octets

SubjectKeyId: 82:f1:40:c4:11:30:54:f3:69:73:85:4e:f5:4d:18:a8:4d:45:11:97
AuthorityKeyId: a8:4a:6a:63:04:7d:dd:ba:e6:d1:39:b7:a6:45:65:ef:f3:a8:ec:a1

Fingerprint (sha1): e1:57:77:88:e1:61:a0:03:b1:ef:c1:a5:9b:56:be:a7:1b:ff:77:04
Fingerprint (sha256): 18:49:54:49:57:0c:74:a1:aa:21:f0:9a:03:0d:6e:99:0b:b1:9d:38:ff:2e:81:cc:b7:a2:6d:c2:a2:97:74:37

Issuing Certificate URL: http://cert.int-x3.letsencrypt.org/

Revocation information

OCSP Server: http://ocsp.int-x3.letsencrypt.org/

Check the revocation status for certificate bel.fi

4

DNS Names

0

Email Addresses

0

IP Addresses

Advanced Certificate Properties

Tehnical certificate details for bel.fi

Public Key Algorithm

RSA

Key Size

2048

Signature Algorithm

SHA256 with RSA

Key Usage

Digital Signature
Key Encipherment

Extended Key Usages

Server Authentication
Client Authentication

Extensions

8 extensions
No unhandled critical extensions

CA Certificate

This is not a CA certificate

Subject Alternative Names

bel.fi
smtp.bel.fi
www.bel.fi
zeus.bel.fi

Other certificates including the domain name bel.fi

(limited to 100 certificates)
bel.fi
eregister.nea.nu
bel.fi
osoitteisto.bel.fi
integraatio.bel.fi
test.osoitteisto.bel.fi
bel.fi
hookedon.bel.fi
verkkolaskuosoite.fi
imsure.report
integraatio.bel.fi
bel.fi
bel.fi
bel.fi
integraatio.bel.fi
bel.fi
rj.bel.fi
bel.fi
bacchus.bel.fi
bacchus.bel.fi
bacchus.bel.fi
hookedon.bel.fi
bacchus.bel.fi
verkkolaskuosoite.fi
bel.fi
hookedon.bel.fi
hookedon.bel.fi
verkkolaskuosoite.fi
bacchus.bel.fi
test.osoitteisto.bel.fi
test.osoitteisto.bel.fi
*.bel.fi
bel.fi
saas.bel.fi
bel.fi
verkkolaskuosoite.fi
verkkolaskuosoite.fi
verkkolaskuosoite.fi
bacchus.bel.fi
integraatio.bel.fi
test.osoitteisto.bel.fi
bel.fi
verkkolaskuosoite.fi
saas.bel.fi
osoitteisto.bel.fi
verkkolaskuosoite.fi
bel.fi
asp2.bel.fi
bel.fi
smtp.bel.fi
hookedon.bel.fi
test.osoitteisto.bel.fi
bel.fi
test.osoitteisto.bel.fi
bel.fi
bel.fi
integraatio.bel.fi
hookedon.bel.fi
bacchus.bel.fi
rj.bel.fi
osoitteisto.bel.fi
bel.fi
verkkolaskuosoite.fi
integraatio.bel.fi
bel.fi
integraatio.bel.fi
bacchus.bel.fi
bel.fi
bel.fi
test.osoitteisto.bel.fi
bacchus.bel.fi
saas.bel.fi
bacchus.bel.fi
bel.fi
test.osoitteisto.bel.fi
bel.fi
saas.bel.fi
bel.fi
bel.fi
hookedon.bel.fi
osoitteisto.bel.fi
saas.bel.fi
rj.bel.fi
bacchus.bel.fi
bel.fi
integraatio.bel.fi
bacchus.bel.fi
hookedon.bel.fi
saas.bel.fi
bacchus.bel.fi
bel.fi
bel.fi
saas.bel.fi
saas.bel.fi
integraatio.bel.fi
rj.bel.fi
saas.bel.fi
bacchus.bel.fi
bel.fi
bel.fi

Certificate

The complete raw certificate details for bel.fi in PEM and ASN.1 format.

Certificate (PEM)

-----BEGIN CERTIFICATE-----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-----END CERTIFICATE-----

Public Key (PEM)

-----BEGIN PUBLIC KEY-----
MIIBIjANBgkqhkiG9w0BAQEFAAOCAQ8AMIIBCgKCAQEAvlu+l75664SIMuLJwyHd
PgvxIpZSyER0wEnEP24ofqn5NzQGfm9SDb5UervU76ZbxTQbdT1khBGTu+kJy/j8
poM5S42/f4ZDGRzAZNxvG53LsZB9RZicT9wpX7Alk0ZSFxkEz9juWUQzyZXxgzvR
i5lDWOyB/fcFhKufdFGej9F1IbQpfynl/zgUZWw7KHy2a1WmNyPHfJzoxsF4J9Fs
omOs3r31lDSVbrAEeNAr78ypPv5k3bxDw9OtMvghah5dkXj0YFljHirWmC+qcaaf
NFqCmxmHr+gkzoEW7wVFJTn/ATScm7DzB9lTUDOJxA5ah12r9djrszpZxWULbD11
HQIDAQAB
-----END PUBLIC KEY-----

ASN.1 decoded

 [c:0|t:16|true] SEQUENCE, SEQUENCE OF 
 . . . . [c:0|t:16|true] SEQUENCE, SEQUENCE OF 
 . . . . . . . . [c:2|t:0|true] OtherName 
 . . . . . . . . . . . . [c:0|t:2|false] INTEGER 2
 . . . . . . . . [c:0|t:2|false] INTEGER 315202271880473264596184292113714656805678
 . . . . . . . . [c:0|t:16|true] SEQUENCE, SEQUENCE OF 
 . . . . . . . . . . . . [c:0|t:6|false] OBJECT IDENTIFIER 1.2.840.113549.1.1.11 (sha256WithRSAEncryption)
 . . . . . . . . . . . . [c:0|t:5|false] NULL 
 . . . . . . . . [c:0|t:16|true] SEQUENCE, SEQUENCE OF 
 . . . . . . . . . . . . [c:0|t:17|true] SET, SET OF 
 . . . . . . . . . . . . . . . . [c:0|t:16|true] SEQUENCE, SEQUENCE OF 
 . . . . . . . . . . . . . . . . . . . . [c:0|t:6|false] OBJECT IDENTIFIER 2.5.4.6 (countryName)
 . . . . . . . . . . . . . . . . . . . . [c:0|t:19|false] PrintableString 'US'
 . . . . . . . . . . . . [c:0|t:17|true] SET, SET OF 
 . . . . . . . . . . . . . . . . [c:0|t:16|true] SEQUENCE, SEQUENCE OF 
 . . . . . . . . . . . . . . . . . . . . [c:0|t:6|false] OBJECT IDENTIFIER 2.5.4.10 (organizationName)
 . . . . . . . . . . . . . . . . . . . . [c:0|t:19|false] PrintableString 'Let's Encrypt'
 . . . . . . . . . . . . [c:0|t:17|true] SET, SET OF 
 . . . . . . . . . . . . . . . . [c:0|t:16|true] SEQUENCE, SEQUENCE OF 
 . . . . . . . . . . . . . . . . . . . . [c:0|t:6|false] OBJECT IDENTIFIER 2.5.4.3 (commonName)
 . . . . . . . . . . . . . . . . . . . . [c:0|t:19|false] PrintableString 'Let's Encrypt Authority X3'
 . . . . . . . . [c:0|t:16|true] SEQUENCE, SEQUENCE OF 
 . . . . . . . . . . . . [c:0|t:23|false] UTCTime 2017-03-26 02:47:00 +0000 UTC
 . . . . . . . . . . . . [c:0|t:23|false] UTCTime 2017-06-24 02:47:00 +0000 UTC
 . . . . . . . . [c:0|t:16|true] SEQUENCE, SEQUENCE OF 
 . . . . . . . . . . . . [c:0|t:17|true] SET, SET OF 
 . . . . . . . . . . . . . . . . [c:0|t:16|true] SEQUENCE, SEQUENCE OF 
 . . . . . . . . . . . . . . . . . . . . [c:0|t:6|false] OBJECT IDENTIFIER 2.5.4.3 (commonName)
 . . . . . . . . . . . . . . . . . . . . [c:0|t:19|false] PrintableString 'bel.fi'
 . . . . . . . . [c:0|t:16|true] SEQUENCE, SEQUENCE OF 
 . . . . . . . . . . . . [c:0|t:16|true] SEQUENCE, SEQUENCE OF 
 . . . . . . . . . . . . . . . . [c:0|t:6|false] OBJECT IDENTIFIER 1.2.840.113549.1.1.1 (rsaEncryption)
 . . . . . . . . . . . . . . . . [c:0|t:5|false] NULL 
 . . . . . . . . . . . . [c:0|t:3|false] BIT STRING (2160 bits)
 . . . . . . . . . . . . . . . . [c:0|t:16|true] SEQUENCE, SEQUENCE OF 
 . . . . . . . . . . . . . . . . . . . . [c:0|t:2|false] INTEGER 24030518844097696492726978968947520168909263599564497131917684165888946514707599338580948789890480487020109385956780130901853341074023678165835484652939189267671050722849369702911986986457821534897449687932603383630539667318730604661933671192406726574151005697808685714564773425639618413637321348475280942793973269511480478862550502987388429307355800003841370087590255610368140911391146768920804862159880891237607619551236536584290184827543524495042538653785154443264193178115428151199109859375875499716756330107085731804003652779090966395248446671723881020496986203678972744566495181756518842118749768244846445557021
 . . . . . . . . . . . . . . . . . . . . [c:0|t:2|false] INTEGER 65537

 . . . . . . . . [c:2|t:3|true] ORAddress 
 . . . . . . . . . . . . [c:0|t:16|true] SEQUENCE, SEQUENCE OF 
 . . . . . . . . . . . . . . . . [c:0|t:16|true] SEQUENCE, SEQUENCE OF 
 . . . . . . . . . . . . . . . . . . . . [c:0|t:6|false] OBJECT IDENTIFIER 2.5.29.15 (keyUsage)
 . . . . . . . . . . . . . . . . . . . . [c:0|t:1|false] BOOLEAN true
 . . . . . . . . . . . . . . . . . . . . [c:0|t:4|false] OCTET STRING (4 bytes)
 . . . . . . . . . . . . . . . . . . . . . . . . [c:0|t:3|false] BIT STRING (3 bits)
							05a0
 . . . . . . . . . . . . . . . . [c:0|t:16|true] SEQUENCE, SEQUENCE OF 
 . . . . . . . . . . . . . . . . . . . . [c:0|t:6|false] OBJECT IDENTIFIER 2.5.29.37 (extKeyUsage)
 . . . . . . . . . . . . . . . . . . . . [c:0|t:4|false] OCTET STRING (22 bytes)
 . . . . . . . . . . . . . . . . . . . . . . . . [c:0|t:16|true] SEQUENCE, SEQUENCE OF 
 . . . . . . . . . . . . . . . . . . . . . . . . . . . . [c:0|t:6|false] OBJECT IDENTIFIER 1.3.6.1.5.5.7.3.1 (serverAuth)
 . . . . . . . . . . . . . . . . . . . . . . . . . . . . [c:0|t:6|false] OBJECT IDENTIFIER 1.3.6.1.5.5.7.3.2 (clientAuth)
 . . . . . . . . . . . . . . . . [c:0|t:16|true] SEQUENCE, SEQUENCE OF 
 . . . . . . . . . . . . . . . . . . . . [c:0|t:6|false] OBJECT IDENTIFIER 2.5.29.19 (basicConstraints)
 . . . . . . . . . . . . . . . . . . . . [c:0|t:1|false] BOOLEAN true
 . . . . . . . . . . . . . . . . . . . . [c:0|t:4|false] OCTET STRING (2 bytes)
 . . . . . . . . . . . . . . . . . . . . . . . . [c:0|t:16|true] SEQUENCE, SEQUENCE OF 
 . . . . . . . . . . . . . . . . [c:0|t:16|true] SEQUENCE, SEQUENCE OF 
 . . . . . . . . . . . . . . . . . . . . [c:0|t:6|false] OBJECT IDENTIFIER 2.5.29.14 (subjectKeyIdentifier)
 . . . . . . . . . . . . . . . . . . . . [c:0|t:4|false] OCTET STRING (22 bytes)
 . . . . . . . . . . . . . . . . . . . . . . . . [c:0|t:4|false] OCTET STRING (20 bytes)
							82f140c4113054f36973854ef54d18a84d451197
 . . . . . . . . . . . . . . . . [c:0|t:16|true] SEQUENCE, SEQUENCE OF 
 . . . . . . . . . . . . . . . . . . . . [c:0|t:6|false] OBJECT IDENTIFIER 2.5.29.35 (authorityKeyIdentifier)
 . . . . . . . . . . . . . . . . . . . . [c:0|t:4|false] OCTET STRING (24 bytes)
 . . . . . . . . . . . . . . . . . . . . . . . . [c:0|t:16|true] SEQUENCE, SEQUENCE OF 
 . . . . . . . . . . . . . . . . . . . . . . . . . . . . [c:2|t:0|false] OtherName a84a6a63047dddbae6d139b7a64565eff3a8eca1
 . . . . . . . . . . . . . . . . [c:0|t:16|true] SEQUENCE, SEQUENCE OF 
 . . . . . . . . . . . . . . . . . . . . [c:0|t:6|false] OBJECT IDENTIFIER 1.3.6.1.5.5.7.1.1 (authorityInfoAccess)
 . . . . . . . . . . . . . . . . . . . . [c:0|t:4|false] OCTET STRING (100 bytes)
 . . . . . . . . . . . . . . . . . . . . . . . . [c:0|t:16|true] SEQUENCE, SEQUENCE OF 
 . . . . . . . . . . . . . . . . . . . . . . . . . . . . [c:0|t:16|true] SEQUENCE, SEQUENCE OF 
 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . [c:0|t:6|false] OBJECT IDENTIFIER 1.3.6.1.5.5.7.48.1 (ocsp)
 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . [c:2|t:6|false] IA5String 'http://ocsp.int-x3.letsencrypt.org/'
 . . . . . . . . . . . . . . . . . . . . . . . . . . . . [c:0|t:16|true] SEQUENCE, SEQUENCE OF 
 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . [c:0|t:6|false] OBJECT IDENTIFIER 1.3.6.1.5.5.7.48.2 (caIssuers)
 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . [c:2|t:6|false] IA5String 'http://cert.int-x3.letsencrypt.org/'
 . . . . . . . . . . . . . . . . [c:0|t:16|true] SEQUENCE, SEQUENCE OF 
 . . . . . . . . . . . . . . . . . . . . [c:0|t:6|false] OBJECT IDENTIFIER 2.5.29.17 (subjectAltName)
 . . . . . . . . . . . . . . . . . . . . [c:0|t:4|false] OCTET STRING (48 bytes)
 . . . . . . . . . . . . . . . . . . . . . . . . [c:0|t:16|true] SEQUENCE, SEQUENCE OF 
 . . . . . . . . . . . . . . . . . . . . . . . . . . . . [c:2|t:2|false] IA5String 'bel.fi'
 . . . . . . . . . . . . . . . . . . . . . . . . . . . . [c:2|t:2|false] IA5String 'smtp.bel.fi'
 . . . . . . . . . . . . . . . . . . . . . . . . . . . . [c:2|t:2|false] IA5String 'www.bel.fi'
 . . . . . . . . . . . . . . . . . . . . . . . . . . . . [c:2|t:2|false] IA5String 'zeus.bel.fi'
 . . . . . . . . . . . . . . . . [c:0|t:16|true] SEQUENCE, SEQUENCE OF 
 . . . . . . . . . . . . . . . . . . . . [c:0|t:6|false] OBJECT IDENTIFIER 2.5.29.32 (certificatePolicies)
 . . . . . . . . . . . . . . . . . . . . [c:0|t:4|false] OCTET STRING (246 bytes)
 . . . . . . . . . . . . . . . . . . . . . . . . [c:0|t:16|true] SEQUENCE, SEQUENCE OF 
 . . . . . . . . . . . . . . . . . . . . . . . . . . . . [c:0|t:16|true] SEQUENCE, SEQUENCE OF 
 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . [c:0|t:6|false] OBJECT IDENTIFIER 2.23.140.1.2.1 (Domain Validation Certificates Policy)
 . . . . . . . . . . . . . . . . . . . . . . . . . . . . [c:0|t:16|true] SEQUENCE, SEQUENCE OF 
 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . [c:0|t:6|false] OBJECT IDENTIFIER 1.3.6.1.4.1.44947.1.1.1
 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . [c:0|t:16|true] SEQUENCE, SEQUENCE OF 
 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . [c:0|t:16|true] SEQUENCE, SEQUENCE OF 
 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . [c:0|t:6|false] OBJECT IDENTIFIER 1.3.6.1.5.5.7.2.1 (cps)
 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . [c:0|t:22|false] IA5String 'http://cps.letsencrypt.org'
 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . [c:0|t:16|true] SEQUENCE, SEQUENCE OF 
 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . [c:0|t:6|false] OBJECT IDENTIFIER 1.3.6.1.5.5.7.2.2 (unotice)
 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . [c:0|t:16|true] SEQUENCE, SEQUENCE OF 
 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . [c:0|t:12|false] UTF8String 'This Certificate may only be relied upon by Relying Parties and only in accordance with the Certificate Policy found at https://letsencrypt.org/repository/'
 . . . . [c:0|t:16|true] SEQUENCE, SEQUENCE OF 
 . . . . . . . . [c:0|t:6|false] OBJECT IDENTIFIER 1.2.840.113549.1.1.11 (sha256WithRSAEncryption)
 . . . . . . . . [c:0|t:5|false] NULL 
 . . . . [c:0|t:3|false] BIT STRING (2048 bits)
		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