www.sjwop.com

Issued by Let's Encrypt Authority X3

About this certificate

This digital certificate with serial number 03:b3:59:e7:c5:67:63:4c:ba:17:11:e5:c4:77:dd:c2:6d:73 was issued on by Let's Encrypt.

With 3 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=www.sjwop.com

Let's Encrypt

Organization: Let's Encrypt
Country: US

This certificate has expire since

Certificate Details

Serial Number (hex): 03:b3:59:e7:c5:67:63:4c:ba:17:11:e5:c4:77:dd:c2:6d:73
Serial Number (int): 322366906190153828389155017354602799590771
Serial Number lenght: 138 bits, 18 octets

SubjectKeyId: fa:ce:78:e2:30:6b:b8:43:86:f9:48:64:df:97:b5:39:aa:d4:97:35
AuthorityKeyId: a8:4a:6a:63:04:7d:dd:ba:e6:d1:39:b7:a6:45:65:ef:f3:a8:ec:a1

Fingerprint (sha1): ca:2a:f3:42:3e:ab:ef:b3:07:b1:51:43:e2:e5:41:b6:ec:cb:1b:8c
Fingerprint (sha256): b5:a7:32:c6:b4:9b:5e:c0:1e:01:e9:2a:f6:de:6d:4f:1d:7e:ea:4c:73:2f:39:6f:f9:cf:dc:df:7c:b9:75:b0

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.sjwop.com

3

DNS Names

0

Email Addresses

0

IP Addresses

Advanced Certificate Properties

Tehnical certificate details for www.sjwop.com

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

sjwop.com
sjwop.ubiquitypress.com
www.sjwop.com

Other certificates including the domain name sjwop.com

(limited to 100 certificates)
www.sjwop.com
sjwop.com
sjwop.com
www.sjwop.com
sjwop.com
www.sjwop.com
www.sjwop.com
www.sjwop.com
www.sjwop.com
account.sjwop.com
www.sjwop.com
www.sjwop.com
www.sjwop.com
www.sjwop.com
sjwop.com
www.sjwop.com
www.sjwop.com
sjwop.com

Certificate

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

Certificate (PEM)

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

Public Key (PEM)

-----BEGIN PUBLIC KEY-----
MIIBIjANBgkqhkiG9w0BAQEFAAOCAQ8AMIIBCgKCAQEAvENMSOJBHZxobOjTtaAo
/cIRhmEtb4Y103NnpMO4uKLHFN+tzv/QyR/eAyFyfsbohjKLj6E0MTmlFisy1Yhy
FlQ5OzvurXDsIeE/QvYXdYY7+I3DBGTXpeyeE7Bl4lfLNV+uBnrGr/gCQYVFslp3
aKplTNdCPXeWW8LtA9Z+/3v1RN/mCv3+ouDKqZr52pq3XuXcEct1QLnmRA/Yu/Ox
DJys2CTqnH6F7Hs64uGRNht+jJgQp4AhhN6y3n7BZf502d8SfI4NsFhz7EocNEdm
HmAapbUTfua1h+926V0D/G1p0zklAmbC3AnKSVXTaHcpcLP7RbqAEFWoZ0SWuebb
+wIDAQAB
-----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 322366906190153828389155017354602799590771
 . . . . . . . . [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 2018-06-08 08:19:52 +0000 UTC
 . . . . . . . . . . . . [c:0|t:23|false] UTCTime 2018-09-06 08:19:52 +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.sjwop.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 (2160 bits)
 . . . . . . . . . . . . . . . . [c:0|t:16|true] SEQUENCE, SEQUENCE OF 
 . . . . . . . . . . . . . . . . . . . . [c:0|t:2|false] INTEGER 23765987207921687521581377878511591858335266949276138962345730257227079350727440621142257879100399426664679524890560229575848386923239768471298423618336357724283932626869524938400207103915313848614093370249157502623576597103173387455473019334317779497309463368682855224704266120136201632143426951764255404617561446732665432601145540912067348022494076293655997768731170603473696258710129852472412841548818246873879634298861886098062709848393399917011691746536671541265455729188332609677775100623996691134490666414876287279663757574675178889542120807936502279818968015490956685554869404467111063220486389183331885833211
 . . . . . . . . . . . . . . . . . . . . [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)
							face78e2306bb84386f94864df97b539aad49735
 . . . . . . . . . . . . . . . . [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 (53 bytes)
 . . . . . . . . . . . . . . . . . . . . . . . . [c:0|t:16|true] SEQUENCE, SEQUENCE OF 
 . . . . . . . . . . . . . . . . . . . . . . . . . . . . [c:2|t:2|false] IA5String 'sjwop.com'
 . . . . . . . . . . . . . . . . . . . . . . . . . . . . [c:2|t:2|false] IA5String 'sjwop.ubiquitypress.com'
 . . . . . . . . . . . . . . . . . . . . . . . . . . . . [c:2|t:2|false] IA5String 'www.sjwop.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 (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 1.3.6.1.4.1.11129.2.4.2
 . . . . . . . . . . . . . . . . . . . . [c:0|t:4|false] OCTET STRING (245 bytes)
 . . . . . . . . . . . . . . . . . . . . . . . . [c:0|t:4|false] OCTET STRING (242 bytes)
							00f0007600db74afeecb29ecb1feca3e716d2ce5b9aabb36f7847183c75d9d4f37b61fbf6400000163deb1ec35000004030047304502201ea05489d7431ba701e3fcbf1a89bba82f555156a34b8da3110c9ce3861bce2202210083447c5286c90981ccfa33be75c17ea85dad7518e8d0ce97fb97cdfbe419cbc9007600293c519654c83965baaa50fc5807d4b76fbf587a2972dca4c30cf4e54547f47800000163deb1ec31000004030047304502205a66c9332664ead7e4e1f9737bd040c65f9de26b09f4b967fb63e830b38e1b7a022100e460c87442152d6b237aa114500f726e7bc51cf819d523245a5644c5130eccb5
 . . . . [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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