booking.lat

Issued by Let's Encrypt Authority X3

About this certificate

This digital certificate with serial number 04:a5:19:84:07:af:89:f5:76:86:0f:a0:7e:4d:e8:5c:6c:7c 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=booking.lat

Let's Encrypt

Organization: Let's Encrypt
Country: US

This certificate has expire since

Certificate Details

Serial Number (hex): 04:a5:19:84:07:af:89:f5:76:86:0f:a0:7e:4d:e8:5c:6c:7c
Serial Number (int): 404629650507960274410463486066734051126396
Serial Number lenght: 139 bits, 18 octets

SubjectKeyId: 44:0b:eb:43:fd:01:81:e5:89:2a:a6:d5:2f:88:f3:45:71:8d:27:7e
AuthorityKeyId: a8:4a:6a:63:04:7d:dd:ba:e6:d1:39:b7:a6:45:65:ef:f3:a8:ec:a1

Fingerprint (sha1): f4:0b:34:fe:bf:ba:62:48:41:70:6b:33:84:ee:cc:cb:50:41:48:46
Fingerprint (sha256): 46:23:e4:b6:ca:03:a3:22:77:50:7d:99:81:78:8e:07:af:ed:fd:46:86:5f:dd:40:ce:49:5f:38:f6:b8:70:cb

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 booking.lat

1

DNS Names

0

Email Addresses

0

IP Addresses

Advanced Certificate Properties

Tehnical certificate details for booking.lat

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

booking.lat

Other certificates including the domain name booking.lat

(limited to 100 certificates)
booking.lat
booking.lat
booking.lat
booking.lat
booking.lat
audiolivros.pt
booking.lat
booking.lat
hispanobonos-com.radicalnames.com

Certificate

The complete raw certificate details for booking.lat 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 404629650507960274410463486066734051126396
 . . . . . . . . [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 2019-10-31 23:45:11 +0000 UTC
 . . . . . . . . . . . . [c:0|t:23|false] UTCTime 2020-01-29 23:45:11 +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 'booking.lat'
 . . . . . . . . [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 950263734930736233195891544003625641425554433557935814221905216261119237136872312229574526457497776078680535854129758625773061904507655842531172973125148252918756093579300219326478534011378640600379496633381751930714409390049337105173005998925676542908622323593868732858832992942992670275263322575138393023047681413639895913238750239455450788294463091684793172250599952981819274780099601784380864489860791266678424504169619504657693380219721658587282176435742504656922210096613634459054339464971311512498812396857545739022830380805577314346131504758215602751157121275950357684839700785378346344505159997274250985128121242402606670279361359758160144998479151439395873723019727891437331683680070961835689178798290099513473924003087724911069467243192042424100206493657906615264220988311085679539237862325043448289632532162260065496759087852225941970001154545786393147699511414202359577978415988134335225263787755098351351970942288899255258274064445427211645005033926092068598172856590498526524512315837983291493750561457773469972108820561737052869985201134472339158543538829867625177075239249967163161046058484887637680835087105487917834547805124402043261654125473930671123424886186841954557349070390117012262650288229185611051968794933
 . . . . . . . . . . . . . . . . . . . . [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)
							440beb43fd0181e5892aa6d52f88f345718d277e
 . . . . . . . . . . . . . . . . [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 (15 bytes)
 . . . . . . . . . . . . . . . . . . . . . . . . [c:0|t:16|true] SEQUENCE, SEQUENCE OF 
 . . . . . . . . . . . . . . . . . . . . . . . . . . . . [c:2|t:2|false] IA5String 'booking.lat'
 . . . . . . . . . . . . . . . . [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 (244 bytes)
 . . . . . . . . . . . . . . . . . . . . . . . . [c:0|t:4|false] OCTET STRING (241 bytes)
							00ef0076006f5376ac31f03119d89900a45115ff77151c11d902c10029068db2089a37d9130000016e246c5b740000040300473045022100e9f35c45ec8676793c7f8afc9c891882e66ebe02415a050122f5f6d32157d31e022063eb95fe548fb57eb025e46a65921147acad2ce1e296091c40a364973aa6d69900750007b75c1be57d68fff1b0c61d2315c7bae6577c5794b76aeebc613a1a69d3a21c0000016e246c5b70000004030046304402207a44567fd28e400f1c3f2a24f9a7a9f13534a465d25d0cdbe6a5a2bc7e5768fb022077d772e2c41507c97f4a7ebaa997ef2e03f88498cb7ee06f9f680d59fb64b570
 . . . . [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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