DV SSL/TLS Certificate for www.du4.co

Certificate is witin its validity period

Issued by Let's Encrypt (R11)

About the www.du4.co DV SSL/TLS Certificate

This certificate with serial number 06:84:ca:38:2c:7a:2e:57:e3:6f:b1:c1:ab:56:d8:b3:85:38 for www.du4.co was issued on by Let's Encrypt.

This DV SSL/TLS Certificate is currently within its validity period but we haven't checked the revocation status of this certificate, you can do this simply on revocationcheck.com. We have found some issues with the compliance of this certificate, they are be shown below. We hope this DV SSL/TLS Certificate review for www.du4.co provides you with the detailed information you were looking for.


We have identified some issues with this certificate:
  • 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)

Let's Encrypt

Organization: Let's Encrypt
Country: US

This X.509 certificate will expire on

Certificate Details

Serial Number (hex): 06:84:ca:38:2c:7a:2e:57:e3:6f:b1:c1:ab:56:d8:b3:85:38
Serial Number (int): 567859783750004188962032037026947333850424
Serial Number Length: 139 bits, 18 octets

Subject Key Identifier: 19:3a:61:1b:8d:f3:1a:7f:81:36:83:3b:ac:c5:5c:be:d3:98:8b:f3
Authority Key Identifier: c5:cf:46:a4:ea:f4:c3:c0:7a:6c:95:c4:2d:b0:5e:92:2f:26:e3:b9

Fingerprint (SHA-1): 4b:a1:6b:ec:a7:50:94:da:5b:80:26:7c:41:59:94:3c:47:6b:cf:e6
Fingerprint (SHA-256): 21:25:2a:c3:d6:0e:4c:33:57:2f:9a:01:4c:03:d3:02:53:5e:1d:56:67:97:31:fe:dd:b2:e2:2c:59:70:70:61

Issuing Certificate URL: http://r11.i.lencr.org/

Revocation Information

CRL Distribution Point: http://r11.c.lencr.org/57.crl

Check the revocation status for certificate www.du4.co
1
DNS Names
0
Email Addresses
0
IP Addresses

Advanced Certificate Properties

Technical details of the X.509 certificate for www.du4.co

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
10
CA Certificate
This is not a CA certificate

Subject Alternative Names

www.du4.co

X.509 Certificate

The complete raw X.509 certificate details for www.du4.co in PEM and ASN.1 format.

Certificate (PEM)

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

Public Key (PEM)

-----BEGIN PUBLIC KEY-----
MIIBIjANBgkqhkiG9w0BAQEFAAOCAQ8AMIIBCgKCAQEAnoJK+r39LMJiLMcAjeyU
pOdyIO+9L0dAVD6jM/aI5r2MPpu+Kxy5BrQOj8mL+YprII2oyTR10sATUOZeyuf7
Ucm5z67UvanY53mREFoMZD5F1AUl+L2JeiQIgAVPBGduEqaLc42Z4lrCQGuZHns1
DBLQRd5yQNUu1Vx5AkaXeZ428/PUngh9OA6CJd3PCqZVmJ1Qd44jG9UeMoYRR5tU
ZO8IZHGSVQq7zI2/vSzVmTn3DimrJuXG5z09JJNnPs4jlEMART1Ix3qiIxByYJgz
6QOvUO0FT9THhBL35r2xzSCwSA/ffcCn4qQPCprHtWOMgpPQMRpa3u6ZYSH1Relj
RwIDAQAB
-----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 567859783750004188962032037026947333850424
 . . . . . . . . [c:0|t:16|true] SEQUENCE, SEQUENCE OF 
 . . . . . . . . . . . . [c:0|t:6|false] OBJECT IDENTIFIER 1.2.840.113549.1.1.11
 . . . . . . . . . . . . [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
 . . . . . . . . . . . . . . . . . . . . [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
 . . . . . . . . . . . . . . . . . . . . [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
 . . . . . . . . . . . . . . . . . . . . [c:0|t:19|false] PrintableString 'R11'
 . . . . . . . . [c:0|t:16|true] SEQUENCE, SEQUENCE OF 
 . . . . . . . . . . . . [c:0|t:23|false] UTCTime 2025-05-30 17:16:50 +0000 UTC
 . . . . . . . . . . . . [c:0|t:23|false] UTCTime 2025-08-28 17:16:49 +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
 . . . . . . . . . . . . . . . . . . . . [c:0|t:19|false] PrintableString 'www.du4.co'
 . . . . . . . . [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
 . . . . . . . . . . . . . . . . [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 20009902002590717699483754879650667316102285296072638664576687317827432063367602798906997316769706587319236229464836111953301717280162445144915715620025976960170260387657894541329717259686937722678368142990842831947245715654578162945428633956433720565499860344152837546930917805930175566771383714606096856954675763284598898255455284872527714275422607704006747823143772629000733620162730443798798758884357125631521004529879582074020078033420006773975125423144439626567879758490881572743949281297787868505077258828951677173815490739687392858864639348689572176982813701369478964584709456267735799924175966521289626706759
 . . . . . . . . . . . . . . . . . . . . [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
 . . . . . . . . . . . . . . . . . . . . [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
 . . . . . . . . . . . . . . . . . . . . [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
 . . . . . . . . . . . . . . . . . . . . . . . . . . . . [c:0|t:6|false] OBJECT IDENTIFIER 1.3.6.1.5.5.7.3.2
 . . . . . . . . . . . . . . . . [c:0|t:16|true] SEQUENCE, SEQUENCE OF 
 . . . . . . . . . . . . . . . . . . . . [c:0|t:6|false] OBJECT IDENTIFIER 2.5.29.19
 . . . . . . . . . . . . . . . . . . . . [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
 . . . . . . . . . . . . . . . . . . . . [c:0|t:4|false] OCTET STRING (22 bytes)
 . . . . . . . . . . . . . . . . . . . . . . . . [c:0|t:4|false] OCTET STRING (20 bytes)
							193a611b8df31a7f8136833bacc55cbed3988bf3
 . . . . . . . . . . . . . . . . [c:0|t:16|true] SEQUENCE, SEQUENCE OF 
 . . . . . . . . . . . . . . . . . . . . [c:0|t:6|false] OBJECT IDENTIFIER 2.5.29.35
 . . . . . . . . . . . . . . . . . . . . [c:0|t:4|false] OCTET STRING (24 bytes)
 . . . . . . . . . . . . . . . . . . . . . . . . [c:0|t:16|true] SEQUENCE, SEQUENCE OF 
 . . . . . . . . . . . . . . . . . . . . . . . . . . . . [c:2|t:0|false] OtherName c5cf46a4eaf4c3c07a6c95c42db05e922f26e3b9
 . . . . . . . . . . . . . . . . [c:0|t:16|true] SEQUENCE, SEQUENCE OF 
 . . . . . . . . . . . . . . . . . . . . [c:0|t:6|false] OBJECT IDENTIFIER 1.3.6.1.5.5.7.1.1
 . . . . . . . . . . . . . . . . . . . . [c:0|t:4|false] OCTET STRING (39 bytes)
 . . . . . . . . . . . . . . . . . . . . . . . . [c:0|t:16|true] SEQUENCE, SEQUENCE OF 
 . . . . . . . . . . . . . . . . . . . . . . . . . . . . [c:0|t:16|true] SEQUENCE, SEQUENCE OF 
 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . [c:0|t:6|false] OBJECT IDENTIFIER 1.3.6.1.5.5.7.48.2
 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . [c:2|t:6|false] IA5String 'http://r11.i.lencr.org/'
 . . . . . . . . . . . . . . . . [c:0|t:16|true] SEQUENCE, SEQUENCE OF 
 . . . . . . . . . . . . . . . . . . . . [c:0|t:6|false] OBJECT IDENTIFIER 2.5.29.17
 . . . . . . . . . . . . . . . . . . . . [c:0|t:4|false] OCTET STRING (14 bytes)
 . . . . . . . . . . . . . . . . . . . . . . . . [c:0|t:16|true] SEQUENCE, SEQUENCE OF 
 . . . . . . . . . . . . . . . . . . . . . . . . . . . . [c:2|t:2|false] IA5String 'www.du4.co'
 . . . . . . . . . . . . . . . . [c:0|t:16|true] SEQUENCE, SEQUENCE OF 
 . . . . . . . . . . . . . . . . . . . . [c:0|t:6|false] OBJECT IDENTIFIER 2.5.29.32
 . . . . . . . . . . . . . . . . . . . . [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
 . . . . . . . . . . . . . . . . [c:0|t:16|true] SEQUENCE, SEQUENCE OF 
 . . . . . . . . . . . . . . . . . . . . [c:0|t:6|false] OBJECT IDENTIFIER 2.5.29.31
 . . . . . . . . . . . . . . . . . . . . [c:0|t:4|false] OCTET STRING (39 bytes)
 . . . . . . . . . . . . . . . . . . . . . . . . [c:0|t:16|true] SEQUENCE, SEQUENCE OF 
 . . . . . . . . . . . . . . . . . . . . . . . . . . . . [c:0|t:16|true] SEQUENCE, SEQUENCE OF 
 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . [c:2|t:0|true] OtherName 
 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . [c:2|t:0|true] OtherName 
 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . [c:2|t:6|false] IA5String 'http://r11.c.lencr.org/57.crl'
 . . . . . . . . . . . . . . . . [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)
							00ef0075000de1f2302bd30dc140621209ea552efc47747cb1d7e930ef0e421eb47e4eaa34000001972267d7f3000004030046304402205d6eecf4c4b9cd6f201ac163c6eb9e9e91ea3632c7fa231c120a7b33cb7fa06902204eedfaef2e8611f70f54f880905f2edb539e2e76e33269d2291798718f0353ff007600dddcca3495d7e11605e79532fac79ff83d1c50dfdb003a1412760a2cacbbc82a000001972267dff00000040300473045022100d3779236b7ceb44c1f8bf8192444e3468bf159d1ff77806809ee6b557c30faec02205c65d0a29cedc7174e68dfe56ab81b67cbae7f6d8cd04e289f6fa50b9610d755
 . . . . [c:0|t:16|true] SEQUENCE, SEQUENCE OF 
 . . . . . . . . [c:0|t:6|false] OBJECT IDENTIFIER 1.2.840.113549.1.1.11
 . . . . . . . . [c:0|t:5|false] NULL []
 . . . . [c:0|t:3|false] BIT STRING (2048 bits)
		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