intent.vc
Issued by R3
About this certificate
This digital certificate with serial number 03:93:79:8a:36:89:58:c4:74:38:a2:2b:62:ca:8c:58:8d:fb was issued on by Let's Encrypt.
With 16 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:
- DV certificate contains a subject common name, this is not recommended. If certificate policy 2.23.140.1.2.1 (CA/B BR domain validated) is included, only country and/or common name is allowed in SubjectDN. (BRs: 7.1.2.7.2)
- Subscriber certificates use of Subject Key Identifier is NOT RECOMMENDED (BRs v2: 7.1.2.7.6)
- Subscriber Certificate: commonName is NOT RECOMMENDED. (BRs: 7.1.2.7.1)
Certificate Subject
CN=intent.vc
Let's Encrypt
Organization:
Let's Encrypt
Country:
US
This certificate has expire since
Certificate Details
Serial Number (hex): 03:93:79:8a:36:89:58:c4:74:38:a2:2b:62:ca:8c:58:8d:fbSerial Number (int): 311519919963246995736630418862975181426171
Serial Number lenght: 138 bits, 18 octets
SubjectKeyId: c8:49:13:e0:6a:1e:68:55:1e:f6:ac:c6:7c:76:d0:1f:ea:db:f9:d7
AuthorityKeyId: 14:2e:b3:17:b7:58:56:cb:ae:50:09:40:e6:1f:af:9d:8b:14:c2:c6
Fingerprint (sha1): 64:af:0a:a6:aa:a7:59:c9:aa:4b:00:fe:ab:02:bf:57:65:5e:1e:35
Fingerprint (sha256): 80:b4:35:4f:1f:50:c6:dc:19:a7:66:2b:df:d8:f9:91:64:eb:e7:b2:e4:9a:a8:6e:43:d5:b4:34:a8:2a:14:3a
Issuing Certificate URL: http://r3.i.lencr.org/
Revocation information
OCSP Server: http://r3.o.lencr.orgCheck the revocation status for certificate intent.vc
16
DNS Names
0
Email Addresses
0
IP Addresses
Advanced Certificate Properties
Tehnical certificate details for intent.vc
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
9 extensions
No
unhandled critical extensions
CA Certificate
This is not a CA certificate
Subject Alternative Names
aiingrid.com.blockchainqatar.com
biglaunchesmatter.com
buyingsellingdomains.com
divinggear.xyz.ggj.co.in
intent.vc
jaycehenline.us
jeanmorency.com
landscpe.com
learningmodels.com
linsday.com
madelynsbakery.com.kentuckyusedchillers.com
rodsandrobots.org
shitdooglussays.com
totalpropertypros.com
undoer.com.whatisyoursource.com
wildlifeartists.org
biglaunchesmatter.com
buyingsellingdomains.com
divinggear.xyz.ggj.co.in
intent.vc
jaycehenline.us
jeanmorency.com
landscpe.com
learningmodels.com
linsday.com
madelynsbakery.com.kentuckyusedchillers.com
rodsandrobots.org
shitdooglussays.com
totalpropertypros.com
undoer.com.whatisyoursource.com
wildlifeartists.org
Other certificates including the domain name intent.vc
(limited to 100 certificates)
Certificate
The complete raw certificate details for intent.vc in PEM and ASN.1 format.
Certificate (PEM)
-----BEGIN CERTIFICATE----- MIIGQzCCBSugAwIBAgISA5N5ijaJWMR0OKIrYsqMWI37MA0GCSqGSIb3DQEBCwUA MDIxCzAJBgNVBAYTAlVTMRYwFAYDVQQKEw1MZXQncyBFbmNyeXB0MQswCQYDVQQD EwJSMzAeFw0yMzEyMjIxNDI4NThaFw0yNDAzMjExNDI4NTdaMBQxEjAQBgNVBAMT CWludGVudC52YzCCASIwDQYJKoZIhvcNAQEBBQADggEPADCCAQoCggEBAMJNHU1D waHzvpLALt3lnnp/3uFxy9Le5ylg6rJcgC52imb+2+CmtIyyLKQoCtqagwoeU0xn DbG2gfGQTe5cVmWbq1zOManix01RqkbVCZ/8tCgwsWQx1ePGdM9NOuwra+KjdEK3 qfi0hFAUD0Rw2TvrXOt9YXxJf+YjA53vzCayPJ8mVT9EFkIyeiW5wqM2gmoplgpt /mD/Mr3aAdVsWptXUvPD29JI4InhLYzPRxeIANSygEoCheNW7hVUJobaU7Dk5aT/ lFpbZhv1I6yBcN8ypLPwWqnoKXOBGCoxa2Kn5X+/Kh4jO2MaFw1UplBhwraxgiMf AVuDELnEFIjoDKkCAwEAAaOCA28wggNrMA4GA1UdDwEB/wQEAwIFoDAdBgNVHSUE FjAUBggrBgEFBQcDAQYIKwYBBQUHAwIwDAYDVR0TAQH/BAIwADAdBgNVHQ4EFgQU yEkT4GoeaFUe9qzGfHbQH+rb+dcwHwYDVR0jBBgwFoAUFC6zF7dYVsuuUAlA5h+v nYsUwsYwVQYIKwYBBQUHAQEESTBHMCEGCCsGAQUFBzABhhVodHRwOi8vcjMuby5s ZW5jci5vcmcwIgYIKwYBBQUHMAKGFmh0dHA6Ly9yMy5pLmxlbmNyLm9yZy8wggF4 BgNVHREEggFvMIIBa4IgYWlpbmdyaWQuY29tLmJsb2NrY2hhaW5xYXRhci5jb22C FWJpZ2xhdW5jaGVzbWF0dGVyLmNvbYIYYnV5aW5nc2VsbGluZ2RvbWFpbnMuY29t ghhkaXZpbmdnZWFyLnh5ei5nZ2ouY28uaW6CCWludGVudC52Y4IPamF5Y2VoZW5s aW5lLnVzgg9qZWFubW9yZW5jeS5jb22CDGxhbmRzY3BlLmNvbYISbGVhcm5pbmdt b2RlbHMuY29tggtsaW5zZGF5LmNvbYIrbWFkZWx5bnNiYWtlcnkuY29tLmtlbnR1 Y2t5dXNlZGNoaWxsZXJzLmNvbYIRcm9kc2FuZHJvYm90cy5vcmeCE3NoaXRkb29n bHVzc2F5cy5jb22CFXRvdGFscHJvcGVydHlwcm9zLmNvbYIfdW5kb2VyLmNvbS53 aGF0aXN5b3Vyc291cmNlLmNvbYITd2lsZGxpZmVhcnRpc3RzLm9yZzATBgNVHSAE DDAKMAgGBmeBDAECATCCAQIGCisGAQQB1nkCBAIEgfMEgfAA7gB1AEiw42vapkc0 D+VqAvqdMOscUgHLVt0sgdm7v6s52IRzAAABjJIk27gAAAQDAEYwRAIgTyayZE8g CTwHAyXx0CCyKkFBRWCmZK3f3OramP+qB1ACIEzsJjH/sWNDJJpZwu/EoAfR8HPt vK3iN8RNswO+zcnQAHUAO1N3dT4tuYBOizBbBv5AO2fYT8P0x70ADS1yb+H61BcA AAGMkiTbvgAABAMARjBEAiA5Ifek5f4eEWdfEWBohOndiHzLR4JTsiKN4khWbFEa /AIgVh1wE2DVrVB4n+EFUrNPVryLfyAYNL6GjTZS9KliTk0wDQYJKoZIhvcNAQEL BQADggEBAKNvSPihn4X6kOb7lr82LN/tN7XlV7OjI6YdXsYCNq+2W9DS8NCN2A/a tSiW4WGfZ/z1r+3340vqLXM8ZTbOlYT56gYb4vtPoeHI56DYeF8SLvQKdGdLL+1v 0eE8iyk+h3+1/a6Y28/+HnPbh5CLw+27xXNxxkpKYSMmkE1gvfdqgYebw2pnpukJ v4nB+lRcBGXeTDhGsEDtFrT2AGmUCX9+NZn/wa8T6jrAD8DQra0zGt7B07nHbvDL o+5QxtXiKKRmbMqtDjFIQApASEFtMukqpL1uTcl9mYLAjN2heHI1f9ZPGtGaIIQe mn3MS0LGurJrmwuE6EWn0f6A4LyagvE= -----END CERTIFICATE-----
Public Key (PEM)
-----BEGIN PUBLIC KEY----- MIIBIjANBgkqhkiG9w0BAQEFAAOCAQ8AMIIBCgKCAQEAwk0dTUPBofO+ksAu3eWe en/e4XHL0t7nKWDqslyALnaKZv7b4Ka0jLIspCgK2pqDCh5TTGcNsbaB8ZBN7lxW ZZurXM4xqeLHTVGqRtUJn/y0KDCxZDHV48Z0z0067Ctr4qN0Qrep+LSEUBQPRHDZ O+tc631hfEl/5iMDne/MJrI8nyZVP0QWQjJ6JbnCozaCaimWCm3+YP8yvdoB1Wxa m1dS88Pb0kjgieEtjM9HF4gA1LKASgKF41buFVQmhtpTsOTlpP+UWltmG/UjrIFw 3zKks/Baqegpc4EYKjFrYqflf78qHiM7YxoXDVSmUGHCtrGCIx8BW4MQucQUiOgM qQIDAQAB -----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 311519919963246995736630418862975181426171 . . . . . . . . [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 'R3' . . . . . . . . [c:0|t:16|true] SEQUENCE, SEQUENCE OF . . . . . . . . . . . . [c:0|t:23|false] UTCTime 2023-12-22 14:28:58 +0000 UTC . . . . . . . . . . . . [c:0|t:23|false] UTCTime 2024-03-21 14:28:57 +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 'intent.vc' . . . . . . . . [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 24528257721016773809388007415311098085036497026141816035233102211133568680281470494275623857381826632218098134536593292997109090385747166452903842702650422061616615793843000520026433294010642558785653140405369485337952793860308408866705229502077514182646797985428818005506028916744889656727779035990764410641744843985084272253580085893585644129526022387148336328810210128633098944077629535443758315338315555794638972597948327818336267206875326329096061128498930647471298656415235426810049818310171132197999614842022702098580374340333777279563124957685550684961047931094330134057886586685085679717248695691559326715049 . . . . . . . . . . . . . . . . . . . . [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) c84913e06a1e68551ef6acc67c76d01feadbf9d7 . . . . . . . . . . . . . . . . [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 142eb317b75856cbae500940e61faf9d8b14c2c6 . . . . . . . . . . . . . . . . [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 (73 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://r3.o.lencr.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://r3.i.lencr.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 (367 bytes) . . . . . . . . . . . . . . . . . . . . . . . . [c:0|t:16|true] SEQUENCE, SEQUENCE OF . . . . . . . . . . . . . . . . . . . . . . . . . . . . [c:2|t:2|false] IA5String 'aiingrid.com.blockchainqatar.com' . . . . . . . . . . . . . . . . . . . . . . . . . . . . [c:2|t:2|false] IA5String 'biglaunchesmatter.com' . . . . . . . . . . . . . . . . . . . . . . . . . . . . [c:2|t:2|false] IA5String 'buyingsellingdomains.com' . . . . . . . . . . . . . . . . . . . . . . . . . . . . [c:2|t:2|false] IA5String 'divinggear.xyz.ggj.co.in' . . . . . . . . . . . . . . . . . . . . . . . . . . . . [c:2|t:2|false] IA5String 'intent.vc' . . . . . . . . . . . . . . . . . . . . . . . . . . . . [c:2|t:2|false] IA5String 'jaycehenline.us' . . . . . . . . . . . . . . . . . . . . . . . . . . . . [c:2|t:2|false] IA5String 'jeanmorency.com' . . . . . . . . . . . . . . . . . . . . . . . . . . . . [c:2|t:2|false] IA5String 'landscpe.com' . . . . . . . . . . . . . . . . . . . . . . . . . . . . [c:2|t:2|false] IA5String 'learningmodels.com' . . . . . . . . . . . . . . . . . . . . . . . . . . . . [c:2|t:2|false] IA5String 'linsday.com' . . . . . . . . . . . . . . . . . . . . . . . . . . . . [c:2|t:2|false] IA5String 'madelynsbakery.com.kentuckyusedchillers.com' . . . . . . . . . . . . . . . . . . . . . . . . . . . . [c:2|t:2|false] IA5String 'rodsandrobots.org' . . . . . . . . . . . . . . . . . . . . . . . . . . . . [c:2|t:2|false] IA5String 'shitdooglussays.com' . . . . . . . . . . . . . . . . . . . . . . . . . . . . [c:2|t:2|false] IA5String 'totalpropertypros.com' . . . . . . . . . . . . . . . . . . . . . . . . . . . . [c:2|t:2|false] IA5String 'undoer.com.whatisyoursource.com' . . . . . . . . . . . . . . . . . . . . . . . . . . . . [c:2|t:2|false] IA5String 'wildlifeartists.org' . . . . . . . . . . . . . . . . [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 (12 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 1.3.6.1.4.1.11129.2.4.2 . . . . . . . . . . . . . . . . . . . . [c:0|t:4|false] OCTET STRING (243 bytes) . . . . . . . . . . . . . . . . . . . . . . . . [c:0|t:4|false] OCTET STRING (240 bytes) 00ee00750048b0e36bdaa647340fe56a02fa9d30eb1c5201cb56dd2c81d9bbbfab39d884730000018c9224dbb8000004030046304402204f26b2644f20093c070325f1d020b22a41414560a664addfdceada98ffaa075002204cec2631ffb16343249a59c2efc4a007d1f073edbcade237c44db303becdc9d00075003b5377753e2db9804e8b305b06fe403b67d84fc3f4c7bd000d2d726fe1fad4170000018c9224dbbe000004030046304402203921f7a4e5fe1e11675f11606884e9dd887ccb478253b2228de248566c511afc0220561d701360d5ad50789fe10552b34f56bc8b7f201834be868d3652f4a9624e4d . . . . [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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