www.zentek.com.br

Issued by R3

About this certificate

This digital certificate with serial number 03:cd:10:c3:7e:12:7c:93:f0:4b:b6:a3:55:0c:e3:ed:ef:60 was issued on by Let's Encrypt.

With 2 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=www.zentek.com.br

Let's Encrypt

Organization: Let's Encrypt
Country: US

This certificate has expire since

Certificate Details

Serial Number (hex): 03:cd:10:c3:7e:12:7c:93:f0:4b:b6:a3:55:0c:e3:ed:ef:60
Serial Number (int): 331117025716941369868662701174200187350880
Serial Number lenght: 138 bits, 18 octets

SubjectKeyId: 06:fc:be:34:85:51:1e:0f:57:f2:25:39:6a:14:32:a1:c5:25:06:31
AuthorityKeyId: 14:2e:b3:17:b7:58:56:cb:ae:50:09:40:e6:1f:af:9d:8b:14:c2:c6

Fingerprint (sha1): 10:d3:05:b4:21:7e:e9:f7:d3:3c:79:ae:7a:7e:0a:aa:5e:6b:8c:0b
Fingerprint (sha256): 85:3b:f5:50:50:c8:73:6a:bf:d0:fe:c3:f3:44:f3:f7:5b:1e:26:0f:18:ef:f2:e9:f8:64:99:7f:1e:0a:84:7e

Issuing Certificate URL: http://r3.i.lencr.org/

Revocation information

OCSP Server: http://r3.o.lencr.org

Check the revocation status for certificate www.zentek.com.br

2

DNS Names

0

Email Addresses

0

IP Addresses

Advanced Certificate Properties

Tehnical certificate details for www.zentek.com.br

Public Key Algorithm

ECDSA

Key Size

256

Signature Algorithm

SHA256 with RSA

Key Usage

Digital Signature

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.zentek.com.br
zentek.com.br

Other certificates including the domain name zentek.com.br

(limited to 100 certificates)

Certificate

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

Certificate (PEM)

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

Public Key (PEM)

-----BEGIN PUBLIC KEY-----
MFkwEwYHKoZIzj0CAQYIKoZIzj0DAQcDQgAE7Pt3VKIm0EgKCCX3BJM3mpNc4KuZ
9AL0/JmKsDMWVTaVN0Ufr3D1jNtpEECh+dm2uZglWpTc24GtQth9AyGSpg==
-----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 331117025716941369868662701174200187350880
 . . . . . . . . [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 2023-11-26 09:00:50 +0000 UTC
 . . . . . . . . . . . . [c:0|t:23|false] UTCTime 2024-02-24 09:00:49 +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 (commonName)
 . . . . . . . . . . . . . . . . . . . . [c:0|t:19|false] PrintableString 'www.zentek.com.br'
 . . . . . . . . [c:0|t:16|true] SEQUENCE, SEQUENCE OF 
 . . . . . . . . . . . . [c:0|t:16|true] SEQUENCE, SEQUENCE OF 
 . . . . . . . . . . . . . . . . [c:0|t:6|false] OBJECT IDENTIFIER 1.2.840.10045.2.1 (ecPublicKey)
 . . . . . . . . . . . . . . . . [c:0|t:6|false] OBJECT IDENTIFIER 1.2.840.10045.3.1.7 (prime256v1)
 . . . . . . . . . . . . [c:0|t:3|false] BIT STRING (520 bits)
				0004ecfb7754a226d0480a0825f70493379a935ce0ab99f402f4fc998ab0331655369537451faf70f58cdb691040a1f9d9b6b998255a94dcdb81ad42d87d032192a6
 . . . . . . . . [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 (1 bits)
							0780
 . . . . . . . . . . . . . . . . [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)
							06fcbe3485511e0f57f225396a1432a1c5250631
 . . . . . . . . . . . . . . . . [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 (36 bytes)
 . . . . . . . . . . . . . . . . . . . . . . . . [c:0|t:16|true] SEQUENCE, SEQUENCE OF 
 . . . . . . . . . . . . . . . . . . . . . . . . . . . . [c:2|t:2|false] IA5String 'www.zentek.com.br'
 . . . . . . . . . . . . . . . . . . . . . . . . . . . . [c:2|t:2|false] IA5String 'zentek.com.br'
 . . . . . . . . . . . . . . . . [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 (245 bytes)
 . . . . . . . . . . . . . . . . . . . . . . . . [c:0|t:4|false] OCTET STRING (242 bytes)
							00f000760048b0e36bdaa647340fe56a02fa9d30eb1c5201cb56dd2c81d9bbbfab39d884730000018c0b1318ca000004030047304502210094e99111968d2c02056eefaa40dc01765f086ef82d3345fb8f3c79e1e2f8453c0220520e23eb6403357d7cc249f0c2bd2bc2c221513b79babc7d200883326c486c2c0076003b5377753e2db9804e8b305b06fe403b67d84fc3f4c7bd000d2d726fe1fad4170000018c0b1318d20000040300473045022030587a01cbf34c61b8c8de94569dd22d7e774eb12096d2b5d638aa374b6e0c0e022100b6e21313311f96aa23c762b6e22364fbf872ec9cc2438d32e913026dc489c60a
 . . . . [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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