487.me

Issued by Let's Encrypt Authority X3

About this certificate

This digital certificate with serial number 03:ba:ca:31:79:df:13:59:88:32:82:75:c9:9f:88:fe:68:48 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=487.me

Let's Encrypt

Organization: Let's Encrypt
Country: US

This certificate has expire since

Certificate Details

Serial Number (hex): 03:ba:ca:31:79:df:13:59:88:32:82:75:c9:9f:88:fe:68:48
Serial Number (int): 324898138992115346092230941865125129119816
Serial Number lenght: 138 bits, 18 octets

SubjectKeyId: 9f:59:38:f6:13:1e:32:d7:cb:e4:11:1b:a4:d2:c9:72:5c:70:6b:93
AuthorityKeyId: a8:4a:6a:63:04:7d:dd:ba:e6:d1:39:b7:a6:45:65:ef:f3:a8:ec:a1

Fingerprint (sha1): 12:de:c2:f9:08:e1:4b:ae:18:ce:de:b8:8b:2d:3a:54:53:66:74:a4
Fingerprint (sha256): 51:5e:c6:38:9c:3b:73:15:1c:85:c9:f3:a1:89:ed:35:c3:d2:b3:71:3b:5b:b5:35:71:51:54:ae:c0:33:92:54

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 487.me

1

DNS Names

0

Email Addresses

0

IP Addresses

Advanced Certificate Properties

Tehnical certificate details for 487.me

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

487.me

Other certificates including the domain name 487.me

(limited to 100 certificates)
champagne.fund
www.487.me
487.me
487.me
487.me
savage-rapids.org
www.487.me
elizabethwarren.life
487.me
www.87892.com
www.487.me
www.487.me
plantbasedprotein.ca
487.me
www.487.me
487.me
487.me
487.me

Certificate

The complete raw certificate details for 487.me 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 324898138992115346092230941865125129119816
 . . . . . . . . [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 2019-09-25 22:27:05 +0000 UTC
 . . . . . . . . . . . . [c:0|t:23|false] UTCTime 2019-12-24 22:27:05 +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 '487.me'
 . . . . . . . . [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 762701381161194653842005874125700389911470915620170936109021533133908676635130703295591854496278704457623192152542238537478499388269752001912083282810681860079580712760707691168987553356983018835097301322796362876436008754949421348943135680391494893968906995044769120627406316313955870565964738786045837404945588506881668269519750530830770347662869848705684013037603521068932548867518302117631575960501750935232459903689007662551223929073944703951267772801476277589712954109411173106905761013319796008645782785969487044849302644884009836879306998355894959033185648109418711181930653005429151624325871551006071674985559014144136686301491897508117209154570347788302630440457676117481659918619139274637172027164972403952370365293647685211458829443059216223258428089492752198755790883292532915292388411774794686180324023172509179257234069920237690513713500135093429228561846839772684691657773686790348312106137027923857678653830478854231419538643760919922843805358699295240445351470976523853010902124009479409733349540161844565446745903104864805033718380251550908373733363808907823881978039855579593315630783054713675232354845766585881324633120948412242426495262522078994649051730946438981204100870215099857132608803152102338021544378037
 . . . . . . . . . . . . . . . . . . . . [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)
							9f5938f6131e32d7cbe4111ba4d2c9725c706b93
 . . . . . . . . . . . . . . . . [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 (10 bytes)
 . . . . . . . . . . . . . . . . . . . . . . . . [c:0|t:16|true] SEQUENCE, SEQUENCE OF 
 . . . . . . . . . . . . . . . . . . . . . . . . . . . . [c:2|t:2|false] IA5String '487.me'
 . . . . . . . . . . . . . . . . [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 (244 bytes)
 . . . . . . . . . . . . . . . . . . . . . . . . [c:0|t:4|false] OCTET STRING (241 bytes)
							00ef007500e2694bae26e8e94009e8861bb63b83d43ee7fe7488fba48f2893019dddf1dbfe0000016d6abfeaae0000040300463044022055bf311387c5ceb3bcefa3d94c93ee4324809f7e8fd606ce02fcb4fdc5278de30220034689d09283d1b70d048e16bb2097f082f9404e021292efdd1b238e16061de5007600293c519654c83965baaa50fc5807d4b76fbf587a2972dca4c30cf4e54547f4780000016d6abfea76000004030047304502200b1cad0705c532546130d0bed9688ddfb54479cff245c77cf12ba40af45aa72c022100dc00f1fefd06d9b35c64f586ef0f8e0fdbedf2fe0ff7fd621e4570c0c3896f31
 . . . . [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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