www.tkl.cz

Issued by R3

About this certificate

This digital certificate with serial number 04:aa:4c:ba:da:61:18:1f:cf:83:ab:d5:f0:00:53:13:a4:59 was issued on by Let's Encrypt.

With 6 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.tkl.cz

Let's Encrypt

Organization: Let's Encrypt
Country: US

This certificate has expire since

Certificate Details

Serial Number (hex): 04:aa:4c:ba:da:61:18:1f:cf:83:ab:d5:f0:00:53:13:a4:59
Serial Number (int): 406399137627753757916391558278965359780953
Serial Number lenght: 139 bits, 18 octets

SubjectKeyId: 3c:ca:e5:e0:b9:b4:f2:d4:1b:1f:63:12:75:33:2b:ed:6e:06:9d:6e
AuthorityKeyId: 14:2e:b3:17:b7:58:56:cb:ae:50:09:40:e6:1f:af:9d:8b:14:c2:c6

Fingerprint (sha1): fa:3f:95:f3:7c:cb:f8:09:ee:90:e6:21:e5:a8:38:d0:f7:21:69:5b
Fingerprint (sha256): 38:51:e8:cb:03:a9:3f:a3:55:19:9b:9b:e7:91:f7:e1:18:f7:e0:8b:c9:cc:74:c9:43:cb:47:a9:c8:6e:db:f6

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

Revocation information

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

Check the revocation status for certificate www.tkl.cz

6

DNS Names

0

Email Addresses

0

IP Addresses

Advanced Certificate Properties

Tehnical certificate details for www.tkl.cz

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

lekarpocitacu.cz
tkl.cz
underscore.cz
www.lekarpocitacu.cz
www.tkl.cz
www.underscore.cz

Other certificates including the domain name tkl.cz

(limited to 100 certificates)
www.tkl.cz
tofu.tkl.cz
www.tkl.cz
tofu.tkl.cz
www.tkl.cz
tofu.tkl.cz
www.tkl.cz
tofu.tkl.cz
www.tkl.cz
www.tkl.cz
tofu.tkl.cz
tofu.tkl.cz
tofu.tkl.cz
www.tkl.cz
tofu.tkl.cz
www.tkl.cz
www.tkl.cz
www.tkl.cz
public.relations.cz
tofu.tkl.cz
tofu.tkl.cz
www.tkl.cz
tofu.tkl.cz
tofu.tkl.cz
tofu.tkl.cz
tofu.tkl.cz
www.tkl.cz
www.tkl.cz
public.relations.cz
tofu.tkl.cz
www.tkl.cz
www.tkl.cz
public.relations.cz
tofu.tkl.cz
tofu.tkl.cz
www.tkl.cz
www.tkl.cz
public.relations.cz
www.tkl.cz
tofu.tkl.cz
tofu.tkl.cz
www.tkl.cz
tofu.tkl.cz
tofu.tkl.cz
tofu.tkl.cz
public.relations.cz
www.tkl.cz
www.tkl.cz
tofu.tkl.cz
public.relations.cz
tofu.tkl.cz
www.tkl.cz
public.relations.cz
www.tkl.cz
www.tkl.cz
tofu.tkl.cz
tofu.tkl.cz
tofu.tkl.cz
public.relations.cz
www.tkl.cz
www.tkl.cz
www.tkl.cz
www.tkl.cz
tofu.tkl.cz
www.tkl.cz
tofu.tkl.cz
tofu.tkl.cz
public.relations.cz
www.tkl.cz
www.tkl.cz
www.tkl.cz
tofu.tkl.cz
tofu.tkl.cz

Certificate

The complete raw certificate details for www.tkl.cz in PEM and ASN.1 format.

Certificate (PEM)

-----BEGIN CERTIFICATE-----
MIIFMjCCBBqgAwIBAgISBKpMutphGB/Pg6vV8ABTE6RZMA0GCSqGSIb3DQEBCwUA
MDIxCzAJBgNVBAYTAlVTMRYwFAYDVQQKEw1MZXQncyBFbmNyeXB0MQswCQYDVQQD
EwJSMzAeFw0yNDAxMjMxOTA1MzNaFw0yNDA0MjIxOTA1MzJaMBUxEzARBgNVBAMT
Cnd3dy50a2wuY3owggEiMA0GCSqGSIb3DQEBAQUAA4IBDwAwggEKAoIBAQDX7vNM
niCVXbvDgPytKXJCUkl4oXNcyFhQYKlx7IzpjQS8zSBY6PaS85X8wLVGze76zYAR
p0O37lyP1OW+kUMTmrwCUXDYqAVn9D2mleWU7SDtk4WNv17DndkcOEbTb5yS6hrS
ubX0Oe+Qbvy70qt84jNxyKPr29DGyrYtUy+EleA7rfB3nWVi02csF1E1AfMvjZuk
y9eaBgsrMKVJtqGVv8jN9agaZUjSKxp4F8q0H5WBfE73lt8WMbBXi/a0Mn72CzRB
nITvTbYbMSvUtk4eTlnwR4iUreBSIZDBQlREZSGlIdD/9NnJRS3HpckWp0JmpyxN
q8AAnOQ0ItG+T/ALAgMBAAGjggJdMIICWTAOBgNVHQ8BAf8EBAMCBaAwHQYDVR0l
BBYwFAYIKwYBBQUHAwEGCCsGAQUFBwMCMAwGA1UdEwEB/wQCMAAwHQYDVR0OBBYE
FDzK5eC5tPLUGx9jEnUzK+1uBp1uMB8GA1UdIwQYMBaAFBQusxe3WFbLrlAJQOYf
r52LFMLGMFUGCCsGAQUFBwEBBEkwRzAhBggrBgEFBQcwAYYVaHR0cDovL3IzLm8u
bGVuY3Iub3JnMCIGCCsGAQUFBzAChhZodHRwOi8vcjMuaS5sZW5jci5vcmcvMGcG
A1UdEQRgMF6CEGxla2FycG9jaXRhY3UuY3qCBnRrbC5jeoINdW5kZXJzY29yZS5j
eoIUd3d3Lmxla2FycG9jaXRhY3UuY3qCCnd3dy50a2wuY3qCEXd3dy51bmRlcnNj
b3JlLmN6MBMGA1UdIAQMMAowCAYGZ4EMAQIBMIIBAwYKKwYBBAHWeQIEAgSB9ASB
8QDvAHUAO1N3dT4tuYBOizBbBv5AO2fYT8P0x70ADS1yb+H61BcAAAGNN+2VewAA
BAMARjBEAiAStlcZBj/DFmm2Y/DoM3MXfWDJqT6FftzfLXStJKQZ/QIgXVgIjBtc
224M1kWyYs8PMWzFvCmUNfoAR9YI0X1cKj4AdgB2/4g/Crb7lVHCYcz1h7o0tKTN
uyncaEIKn+ZnTFo6dAAAAY037ZXeAAAEAwBHMEUCIBqZsceYh6ndRrFfHOgnxkxs
pYl37PSsm24/JQbxWh+XAiEArS+/4sJbm8tdXowL9nQXlVmdzpxLKNBIJ+FZDgI4
Q1gwDQYJKoZIhvcNAQELBQADggEBALISF8cgJaUzVeyM2aH/e1u3jtO/fpcau3Le
AixGClvtHYMJr6WTPTX0YsbSkRtj7Gq3f0NjfJLPL/hmRAZNK/m1HW8xe5Z+BVEU
S/Kj8r8ZVy+6Cxrg6OD28UNvCRPaTK1IShHvh/d4gRSmoToUvZc/zjwfNZeKwEV6
8lkmETZrDoMUmHJc4zr4ui4lFhxXvCQrf4htk4+sHNeqt2wcoNLgMzuDZvWmYI4a
o/9XKFbId5DPPcv+kXQWnB0UDOhKMVeQyOeRCjMyDhKw/IeX/f2nImJKYZG73VE2
pan0Lj+VC1LCp5DzzSQbT2/SXjpfOg9Z7xJzo5OA3rg6qWsEMCA=
-----END CERTIFICATE-----

Public Key (PEM)

-----BEGIN PUBLIC KEY-----
MIIBIjANBgkqhkiG9w0BAQEFAAOCAQ8AMIIBCgKCAQEA1+7zTJ4glV27w4D8rSly
QlJJeKFzXMhYUGCpceyM6Y0EvM0gWOj2kvOV/MC1Rs3u+s2AEadDt+5cj9TlvpFD
E5q8AlFw2KgFZ/Q9ppXllO0g7ZOFjb9ew53ZHDhG02+ckuoa0rm19DnvkG78u9Kr
fOIzccij69vQxsq2LVMvhJXgO63wd51lYtNnLBdRNQHzL42bpMvXmgYLKzClSbah
lb/IzfWoGmVI0isaeBfKtB+VgXxO95bfFjGwV4v2tDJ+9gs0QZyE7022GzEr1LZO
Hk5Z8EeIlK3gUiGQwUJURGUhpSHQ//TZyUUtx6XJFqdCZqcsTavAAJzkNCLRvk/w
CwIDAQAB
-----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 406399137627753757916391558278965359780953
 . . . . . . . . [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 2024-01-23 19:05:33 +0000 UTC
 . . . . . . . . . . . . [c:0|t:23|false] UTCTime 2024-04-22 19:05:32 +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.tkl.cz'
 . . . . . . . . [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 27259066395563126688569472007989351200846911297687051839476382415582031770516722162915529225586433067239309077375395160302027721509749979178230211327320466251024368564981136036017064941593361715658821819854125349261261530324017966710932221687840194638887985867799577780743912021769825241473990967892823103300112309359308878516237378048947857791416394761306307181089838064095168825543261127204201173153470902762105023740579038319068137259021866652612905345565187951154170065572710668362750832499178162833707343870930968752987782603307662821439912620847612461797579748817210520855598582503769360368174283584144457854987
 . . . . . . . . . . . . . . . . . . . . [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)
							3ccae5e0b9b4f2d41b1f631275332bed6e069d6e
 . . . . . . . . . . . . . . . . [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 (96 bytes)
 . . . . . . . . . . . . . . . . . . . . . . . . [c:0|t:16|true] SEQUENCE, SEQUENCE OF 
 . . . . . . . . . . . . . . . . . . . . . . . . . . . . [c:2|t:2|false] IA5String 'lekarpocitacu.cz'
 . . . . . . . . . . . . . . . . . . . . . . . . . . . . [c:2|t:2|false] IA5String 'tkl.cz'
 . . . . . . . . . . . . . . . . . . . . . . . . . . . . [c:2|t:2|false] IA5String 'underscore.cz'
 . . . . . . . . . . . . . . . . . . . . . . . . . . . . [c:2|t:2|false] IA5String 'www.lekarpocitacu.cz'
 . . . . . . . . . . . . . . . . . . . . . . . . . . . . [c:2|t:2|false] IA5String 'www.tkl.cz'
 . . . . . . . . . . . . . . . . . . . . . . . . . . . . [c:2|t:2|false] IA5String 'www.underscore.cz'
 . . . . . . . . . . . . . . . . [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 (244 bytes)
 . . . . . . . . . . . . . . . . . . . . . . . . [c:0|t:4|false] OCTET STRING (241 bytes)
							00ef0075003b5377753e2db9804e8b305b06fe403b67d84fc3f4c7bd000d2d726fe1fad4170000018d37ed957b0000040300463044022012b65719063fc31669b663f0e83373177d60c9a93e857edcdf2d74ad24a419fd02205d58088c1b5cdb6e0cd645b262cf0f316cc5bc299435fa0047d608d17d5c2a3e00760076ff883f0ab6fb9551c261ccf587ba34b4a4cdbb29dc68420a9fe6674c5a3a740000018d37ed95de000004030047304502201a99b1c79887a9dd46b15f1ce827c64c6ca58977ecf4ac9b6e3f2506f15a1f97022100ad2fbfe2c25b9bcb5d5e8c0bf6741795599dce9c4b28d04827e1590e02384358
 . . . . [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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