www.dynavalve.com
Issued by Let's Encrypt Authority X3
About this certificate
This digital certificate with serial number 03:e6:f6:6b:6a:83:64:4a:98:c8:26:05:a8:34:59:12:8b:1e 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.dynavalve.com
Let's Encrypt
Organization:
Let's Encrypt
Country:
US
This certificate has expire since
Certificate Details
Serial Number (hex): 03:e6:f6:6b:6a:83:64:4a:98:c8:26:05:a8:34:59:12:8b:1eSerial Number (int): 339929350010168885027168720661254260296478
Serial Number lenght: 138 bits, 18 octets
SubjectKeyId: e8:fb:13:7b:0f:c4:3f:f0:e1:af:0d:28:c5:b8:03:85:87:36:c7:d9
AuthorityKeyId: a8:4a:6a:63:04:7d:dd:ba:e6:d1:39:b7:a6:45:65:ef:f3:a8:ec:a1
Fingerprint (sha1): 84:d2:03:29:ce:5d:85:14:78:0d:49:7f:15:5c:aa:02:18:5c:3e:e8
Fingerprint (sha256): e1:7c:02:ad:2e:a8:dd:4c:c3:b5:36:5d:1e:29:8e:15:27:4e:71:ed:df:da:a2:8e:1c:e4:b7:ef:c7:84:6c:d0
Issuing Certificate URL: http://cert.int-x3.letsencrypt.org/
Revocation information
OCSP Server: http://ocsp.int-x3.letsencrypt.orgCheck the revocation status for certificate www.dynavalve.com
1
DNS Names
0
Email Addresses
0
IP Addresses
Advanced Certificate Properties
Tehnical certificate details for www.dynavalve.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.dynavalve.com
Other certificates including the domain name dynavalve.com
(limited to 100 certificates)
myra.org
dynavalve.com
dynavalve.com
calif.life
southeroakspropertyservice.com
www.portablemate.com
dynavalve.com
dynavalve.com
dynavalve.com
teddybears.world
www.dynavalve.com
www.dynavalve.com
www.aiqiong.com
www.prasiolite.com
solendra.com
www.dynavalve.com
sensordyne.com
www.surelysilk.com
www.compassam.com
dynavalve.com
dynavalve.com
calif.life
southeroakspropertyservice.com
www.portablemate.com
dynavalve.com
dynavalve.com
dynavalve.com
teddybears.world
www.dynavalve.com
www.dynavalve.com
www.aiqiong.com
www.prasiolite.com
solendra.com
www.dynavalve.com
sensordyne.com
www.surelysilk.com
www.compassam.com
Certificate
The complete raw certificate details for www.dynavalve.com in PEM and ASN.1 format.
Certificate (PEM)
-----BEGIN CERTIFICATE----- MIIGXDCCBUSgAwIBAgISA+b2a2qDZEqYyCYFqDRZEoseMA0GCSqGSIb3DQEBCwUA MEoxCzAJBgNVBAYTAlVTMRYwFAYDVQQKEw1MZXQncyBFbmNyeXB0MSMwIQYDVQQD ExpMZXQncyBFbmNyeXB0IEF1dGhvcml0eSBYMzAeFw0yMDAyMTkwMjM5MzFaFw0y MDA1MTkwMjM5MzFaMBwxGjAYBgNVBAMTEXd3dy5keW5hdmFsdmUuY29tMIICIjAN BgkqhkiG9w0BAQEFAAOCAg8AMIICCgKCAgEA85hlbmK9Fvzq79I8a0qQL3Ok4iMT mAZBsrzEwx6/Ow0fpg+jBAiWey9iXHDwUXdnROSyhe+lMruL8YQSr80BI7L0ZLV7 AjA2feLFmNtlqWAs33WbpI5eMM3tjfpU1b6lF62b7G/oxdYHiqsD51AsW3v49O37 yp8NmRCDJs5I7uDEAuX7IBa1j+hLFzCQYnYKYQsVbs7dG0IOetwkCAhLcRJgqrpZ oXO08FrCC67/1Ftj7XYB/lO+VSr52HjU8Bu+JP8F7TFZSvBBXSJ0LLQg+AFJ2L9D 58NdlYF86vziKGmHUQLLVA6ZS7JYmMkfIdR9zw/XdXNLwiWdB2M0UwsAEd9yXkl5 hYowRaCY0q644MAMqkZIDW0bTo1EDtPg+sgKF/xviXGE4UCydPqwpH066DY5yjnp YmD+eNOw94yfOwV6vCzYj2s5xfL6wBUCEGs/3PinVuVcHj9XHx8dfqtVLRZDOcSa dzh9hRbxqwGfad9u51N8g7+6zv0GljYMM7raXlNLHFmBuifu9mzSQ1qV/XoLiRPi chQ88i6qLDIQKz2XDiapJrtqiyczyoKNIa7Mc/mNHV3gnQap+lVUwe/Xsjn4PlVD XvbGE/Z3yI86MzmyT98ueQ+26n351m4wQeCVz1GwJuG/Hbtf0224UhusHlAdnKtK uJB2bVYuxS0OYP0CAwEAAaOCAmgwggJkMA4GA1UdDwEB/wQEAwIFoDAdBgNVHSUE FjAUBggrBgEFBQcDAQYIKwYBBQUHAwIwDAYDVR0TAQH/BAIwADAdBgNVHQ4EFgQU 6PsTew/EP/Dhrw0oxbgDhYc2x9kwHwYDVR0jBBgwFoAUqEpqYwR93brm0Tm3pkVl 7/Oo7KEwbwYIKwYBBQUHAQEEYzBhMC4GCCsGAQUFBzABhiJodHRwOi8vb2NzcC5p bnQteDMubGV0c2VuY3J5cHQub3JnMC8GCCsGAQUFBzAChiNodHRwOi8vY2VydC5p bnQteDMubGV0c2VuY3J5cHQub3JnLzAcBgNVHREEFTATghF3d3cuZHluYXZhbHZl LmNvbTBMBgNVHSAERTBDMAgGBmeBDAECATA3BgsrBgEEAYLfEwEBATAoMCYGCCsG AQUFBwIBFhpodHRwOi8vY3BzLmxldHNlbmNyeXB0Lm9yZzCCAQYGCisGAQQB1nkC BAIEgfcEgfQA8gB3APCVpFnyANGCQBAtL5OIjq1L/h1H45nh0DSmsKiqjrJzAAAB cFuHfoEAAAQDAEgwRgIhAIr+DM06HOepHjqjfmYBvwlZF/mkQhLodUVzJrmEr+KC AiEAhgGBvc/VA5ZPmsJ0j6K90YOCUpfSQhhrXffWgvvNVy0AdwCyHgXMi6LNiiBO h2b5K7mKJSBna9r6cOeySVMt74uQXgAAAXBbh35yAAAEAwBIMEYCIQDOqZrTPS6z TKgJzTnMHfJdBtYHv3EUM+j3lAklhkbXkwIhALx+1Twd+UklwoZdGdqS+N17hAEx qCWUBjPNeeAR84KcMA0GCSqGSIb3DQEBCwUAA4IBAQAxyEVVgGgR7MRYgrKziixK MUyf3JTLsRALrntpb+L/HfN7PldWkTeQTCyv8/ype/MmDkW/Ouv2UqM4ZVYg8MmI HD+wWIh26kcSiEowhQTfgUOce4K//qLtQbuFjmdQau4Ppa+578Xv+981gMN5iD1Z qjDnTwFyX0NJ484rQUkAGs1eH/ieDT1VJqHsCBusyW/HSvBqQuNu5rxbK+noJ/0J rMBTJlioXEGMGmLtWqYXSZeTJ3st/Tt2TkIA1xeYJFgm4ESlToynnmtAvl6w9Sh+ nHp2fdAUS8L0Q1ePC3o5CD5kHjY488LvcQCPjZUfdb+cM3m7ig3mUN5Y+aUfUCWj -----END CERTIFICATE-----
Public Key (PEM)
-----BEGIN PUBLIC KEY----- MIICIjANBgkqhkiG9w0BAQEFAAOCAg8AMIICCgKCAgEA85hlbmK9Fvzq79I8a0qQ L3Ok4iMTmAZBsrzEwx6/Ow0fpg+jBAiWey9iXHDwUXdnROSyhe+lMruL8YQSr80B I7L0ZLV7AjA2feLFmNtlqWAs33WbpI5eMM3tjfpU1b6lF62b7G/oxdYHiqsD51As W3v49O37yp8NmRCDJs5I7uDEAuX7IBa1j+hLFzCQYnYKYQsVbs7dG0IOetwkCAhL cRJgqrpZoXO08FrCC67/1Ftj7XYB/lO+VSr52HjU8Bu+JP8F7TFZSvBBXSJ0LLQg +AFJ2L9D58NdlYF86vziKGmHUQLLVA6ZS7JYmMkfIdR9zw/XdXNLwiWdB2M0UwsA Ed9yXkl5hYowRaCY0q644MAMqkZIDW0bTo1EDtPg+sgKF/xviXGE4UCydPqwpH06 6DY5yjnpYmD+eNOw94yfOwV6vCzYj2s5xfL6wBUCEGs/3PinVuVcHj9XHx8dfqtV LRZDOcSadzh9hRbxqwGfad9u51N8g7+6zv0GljYMM7raXlNLHFmBuifu9mzSQ1qV /XoLiRPichQ88i6qLDIQKz2XDiapJrtqiyczyoKNIa7Mc/mNHV3gnQap+lVUwe/X sjn4PlVDXvbGE/Z3yI86MzmyT98ueQ+26n351m4wQeCVz1GwJuG/Hbtf0224Uhus HlAdnKtKuJB2bVYuxS0OYP0CAwEAAQ== -----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 339929350010168885027168720661254260296478 . . . . . . . . [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 2020-02-19 02:39:31 +0000 UTC . . . . . . . . . . . . [c:0|t:23|false] UTCTime 2020-05-19 02:39:31 +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.dynavalve.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 993782111329553878156194066870823362507262590165635801198710053567134544209616947984308436427214123881953420314674219326914663679090421940199956988414299857312203983845387453310755944201343477021711579356383917753179703926143537368373811977668949654500901730402491903693783718961933073676259996206290762480631254966889081945836010614579213035150790153905885946767953990442691139882718807020256462712401956190665149796095544074802250476332913826499588089052444987027209182420540799723482251156815020695761764469958149838231964774928918018822450189505194396299125426697459777601722762561220050008463952246139312696572162649203290872529690783071892390800760564027343884676746816520850321284408572014828581579818798986209458876104807328058419248107672248904082747883327137975358964026193029761800732094523710612426269943123501162021312392974645261906853685010785415074724936461759700498901873151975640776937766422594346023345849660316549874610897561841379091231737170670719658647298581859781063688706201192691644178807885312780289509620380483103462633819535592535706595395298195627682345260053861477238296590295648950361643187099089463129160929887042786318746177901717304891320114884234102973587344081027725234916570745574555212598632701 . . . . . . . . . . . . . . . . . . . . [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) e8fb137b0fc43ff0e1af0d28c5b803858736c7d9 . . . . . . . . . . . . . . . . [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 (21 bytes) . . . . . . . . . . . . . . . . . . . . . . . . [c:0|t:16|true] SEQUENCE, SEQUENCE OF . . . . . . . . . . . . . . . . . . . . . . . . . . . . [c:2|t:2|false] IA5String 'www.dynavalve.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 (247 bytes) . . . . . . . . . . . . . . . . . . . . . . . . [c:0|t:4|false] OCTET STRING (244 bytes) 00f2007700f095a459f200d18240102d2f93888ead4bfe1d47e399e1d034a6b0a8aa8eb273000001705b877e8100000403004830460221008afe0ccd3a1ce7a91e3aa37e6601bf095917f9a44212e875457326b984afe282022100860181bdcfd503964f9ac2748fa2bdd183825297d242186b5df7d682fbcd572d007700b21e05cc8ba2cd8a204e8766f92bb98a2520676bdafa70e7b249532def8b905e000001705b877e720000040300483046022100cea99ad33d2eb34ca809cd39cc1df25d06d607bf711433e8f79409258646d793022100bc7ed53c1df94925c2865d19da92f8dd7b840131a825940633cd79e011f3829c . . . . [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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