cruiser-superstore.com

Issued by Let's Encrypt Authority X3

About this certificate

This digital certificate with serial number 03:50:b8:5a:66:7b:36:a8:0b:da:50:37:63:26:80:64:fc:f2 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=cruiser-superstore.com

Let's Encrypt

Organization: Let's Encrypt
Country: US

This certificate has expire since

Certificate Details

Serial Number (hex): 03:50:b8:5a:66:7b:36:a8:0b:da:50:37:63:26:80:64:fc:f2
Serial Number (int): 288804494485465268579808681721237229337842
Serial Number lenght: 138 bits, 18 octets

SubjectKeyId: d3:e3:d3:f3:f8:a2:55:f0:db:cb:7c:4c:0a:91:7b:80:b5:24:51:fb
AuthorityKeyId: a8:4a:6a:63:04:7d:dd:ba:e6:d1:39:b7:a6:45:65:ef:f3:a8:ec:a1

Fingerprint (sha1): e1:35:32:66:57:54:07:dc:45:bb:f4:a6:d2:ec:d5:2f:36:0a:d5:e6
Fingerprint (sha256): cc:85:88:1e:da:c8:91:55:d4:05:61:9a:fa:32:02:28:4d:f8:bf:a4:3f:9b:32:c6:a7:25:62:3e:f0:f2:49:ba

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 cruiser-superstore.com

1

DNS Names

0

Email Addresses

0

IP Addresses

Advanced Certificate Properties

Tehnical certificate details for cruiser-superstore.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

cruiser-superstore.com

Other certificates including the domain name cruiser-superstore.com

(limited to 100 certificates)

Certificate

The complete raw certificate details for cruiser-superstore.com in PEM and ASN.1 format.

Certificate (PEM)

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

Public Key (PEM)

-----BEGIN PUBLIC KEY-----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-----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 288804494485465268579808681721237229337842
 . . . . . . . . [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 2019-05-31 05:32:15 +0000 UTC
 . . . . . . . . . . . . [c:0|t:23|false] UTCTime 2019-08-29 05:32:15 +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 'cruiser-superstore.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 836429584034796865624946382979432266944893243455418816735303531816225387005833174157849755532963526698000571091524133217820096953023277994329402146369009033580906003190693890846493163967172078502773755805313144967334368335183888262810445751880717505022065175466746244725711063266227771130828482986157518299419581547425632525685808488388856878340891840917172263443352574866119809164343882287568807396210345702673416956435889784833969728965378373163922870241418120483571302289806592279305294738984391517707421589317076632203944306702003217010020973632812841217639986818493542964675978588228230898879765951702809410761377630358785486639335802715845217585498686374149039589570664067032094572616747610365909578525168912594363449294647103457721772395904223942008179585084674487085408007098395154162369131181285393810577263241947373406242923739943448032535434221455480009067362187135103384324332543185598024276881030234955544962484956579760120496170480286805396123561690887107557501779487550045512137230971303866388827581257113525106164298709486718630362571833354781569172379017748280225288741308875412877601595242649158843566177944193566915128879174018900249394389040575752542736500502025738558805874681882748811430736477149846041549085209
 . . . . . . . . . . . . . . . . . . . . [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)
							d3e3d3f3f8a255f0dbcb7c4c0a917b80b52451fb
 . . . . . . . . . . . . . . . . [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 (26 bytes)
 . . . . . . . . . . . . . . . . . . . . . . . . [c:0|t:16|true] SEQUENCE, SEQUENCE OF 
 . . . . . . . . . . . . . . . . . . . . . . . . . . . . [c:2|t:2|false] IA5String 'cruiser-superstore.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 (246 bytes)
 . . . . . . . . . . . . . . . . . . . . . . . . [c:0|t:4|false] OCTET STRING (243 bytes)
							00f1007700e2694bae26e8e94009e8861bb63b83d43ee7fe7488fba48f2893019dddf1dbfe0000016b0c96c57e0000040300483046022100cae056d1c216c4a2db1e5ff1470a0a78069b18e6eccd36b094c81f32a9a3433a022100d6feb77861eb38dfa7e315b7953d01274208a38ff9522662faec333c39985e3900760063f2dbcde83bcc2ccf0b728427576b33a48d61778fbd75a638b1c768544bd88d0000016b0c96c7940000040300473045022000a858e236a64b4340464c76167300d6d92dd6c3396bd22da5f4a1047559d453022100bb37028ffbbd59af7cfe2fdd6ad20060cbc48d6c021d0f851e9e9d71a3f6f482
 . . . . [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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