www.87215.com

Issued by Let's Encrypt Authority X3

About this certificate

This digital certificate with serial number 04:78:65:28:c9:ac:48:2b:57:99:2a:fb:65:05:da:30:0c:40 was issued on by Let's Encrypt.

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=www.87215.com

Let's Encrypt

Organization: Let's Encrypt
Country: US

This certificate has expire since

Certificate Details

Serial Number (hex): 04:78:65:28:c9:ac:48:2b:57:99:2a:fb:65:05:da:30:0c:40
Serial Number (int): 389417491567416129702996911221555334220864
Serial Number lenght: 139 bits, 18 octets

SubjectKeyId: a6:b7:7b:85:4c:96:47:d6:84:37:68:46:21:5b:3d:6e:0d:e6:41:ca
AuthorityKeyId: a8:4a:6a:63:04:7d:dd:ba:e6:d1:39:b7:a6:45:65:ef:f3:a8:ec:a1

Fingerprint (sha1): 5a:61:0a:72:10:c4:6f:b6:e9:98:c8:03:dd:58:ed:eb:9a:38:e7:59
Fingerprint (sha256): 83:9d:85:51:ef:f1:c6:85:b8:88:e2:4e:15:bc:dd:1a:ca:2d:bf:f6:5f:fe:18:a3:28:fc:78:67:50:64:3d:cf

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 www.87215.com

1

DNS Names

0

Email Addresses

0

IP Addresses

Advanced Certificate Properties

Tehnical certificate details for www.87215.com

Public Key Algorithm

RSA

Key Size

4096

Signature Algorithm

SHA256 with RSA

Key Usage

Digital Signature
Key Encipherment

Extended Key Usages

Server Authentication
Client Authentication

Extensions

9 extensions
No unhandled critical extensions

CA Certificate

This is not a CA certificate

Subject Alternative Names

www.87215.com

Other certificates including the domain name 87215.com

(limited to 100 certificates)
87215.com
www.39783.com
www.87215.com
87215.com
www.82573.com
www.77823.com
www.87215.com
www.87215.com
87215.com
www.87215.com
www.loyaloffice.com
www.87215.com
87215.com
www.87215.com
87215.com
87215.com
87215.com
87215d.com

Certificate

The complete raw certificate details for www.87215.com in PEM and ASN.1 format.

Certificate (PEM)

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

Public Key (PEM)

-----BEGIN PUBLIC KEY-----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-----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 389417491567416129702996911221555334220864
 . . . . . . . . [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 2019-10-29 16:54:29 +0000 UTC
 . . . . . . . . . . . . [c:0|t:23|false] UTCTime 2020-01-27 16:54:29 +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 'www.87215.com'
 . . . . . . . . [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 (4208 bits)
 . . . . . . . . . . . . . . . . [c:0|t:16|true] SEQUENCE, SEQUENCE OF 
 . . . . . . . . . . . . . . . . . . . . [c:0|t:2|false] INTEGER 786015175901338936700853979301018998030789569172675002184335851216972443297958927003565907063273151447285289482588994730569314829013258529194957262690728625469589406474316926982883821575781193031398580710529941738975137650836100619284512421278294821274371694896732232030425043119005774925221988427535020124080493235279897240130459635514614456699926696992768616433906242349014732077191234690476482053006456912796255826379518619415912418798472396425092823799420678812137599621541351368686774413828204196727681692497690084120458054815870811898633283341825953143447620168653305179816439990980053187072895556383821819186863517927952845878914561582807410741378186045703879801428256740722674888357829333782170223667319584496009364134176390551831397430207382118846825882622541409606477935773616577880420756136264395329151192844301153460796790154853177764518011930453856957502501686391946667561294363229453535517716722945555364985873169902974240519824695633877789128381645086612590493539156463772526186883625163931730757024444735357877773547823201114711124785974178694691365277435785817312646392078838754938860473747632147552468949772127974618241152867935190053387384196235184583335350558465902612971844413464285583053303411421457834254870609
 . . . . . . . . . . . . . . . . . . . . [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)
							a6b77b854c9647d684376846215b3d6e0de641ca
 . . . . . . . . . . . . . . . . [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 (99 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 (17 bytes)
 . . . . . . . . . . . . . . . . . . . . . . . . [c:0|t:16|true] SEQUENCE, SEQUENCE OF 
 . . . . . . . . . . . . . . . . . . . . . . . . . . . . [c:2|t:2|false] IA5String 'www.87215.com'
 . . . . . . . . . . . . . . . . [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 (69 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 1.3.6.1.4.1.11129.2.4.2
 . . . . . . . . . . . . . . . . . . . . [c:0|t:4|false] OCTET STRING (245 bytes)
 . . . . . . . . . . . . . . . . . . . . . . . . [c:0|t:4|false] OCTET STRING (242 bytes)
							00f00076006f5376ac31f03119d89900a45115ff77151c11d902c10029068db2089a37d9130000016e18a7a186000004030047304502204cb75613db093c9fb27c7651e99291f58277e5f2b5b9c379298950aedb9c10ac022100d7a2de7306472e85d81062ab058c7e490cf1e2735b9aa0e1fea76d44322705c0007600b21e05cc8ba2cd8a204e8766f92bb98a2520676bdafa70e7b249532def8b905e0000016e18a7a151000004030047304502200f738119d381634cd0f6a8aababb6a637db673a75b7685f2311daf61939d3f13022100e2b033120d6e5da28b6cc965578c892026c85c10ad4236256d9a71c319e5142a
 . . . . [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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