link.bg

Issued by Let's Encrypt Authority X3

About this certificate

This digital certificate with serial number 03:3a:f8:9e:43:cd:8a:8c:08:ea:f2:0d:ae:fa:4b:74:c5:4d 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:
  • Subscriber Certificate: commonName is deprecated. (BRs: 7.1.4.2.2)

Certificate Subject

CN=link.bg

Let's Encrypt

Organization: Let's Encrypt
Country: US

This certificate has expire since

Certificate Details

Serial Number (hex): 03:3a:f8:9e:43:cd:8a:8c:08:ea:f2:0d:ae:fa:4b:74:c5:4d
Serial Number (int): 281403705377759573443161988752248013112653
Serial Number lenght: 138 bits, 18 octets

SubjectKeyId: c0:a6:6e:ef:4d:db:3d:a1:b3:98:32:f4:3d:a6:9f:7f:5c:1f:74:46
AuthorityKeyId: a8:4a:6a:63:04:7d:dd:ba:e6:d1:39:b7:a6:45:65:ef:f3:a8:ec:a1

Fingerprint (sha1): 15:c0:ea:55:88:45:84:a9:f1:41:a9:eb:9e:82:57:fc:8b:97:89:f3
Fingerprint (sha256): 95:a8:51:77:4d:59:b8:d9:4b:91:5d:88:fc:aa:35:d5:21:f2:b9:0e:25:54:44:50:0a:1b:68:ea:95:04:e5:82

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 link.bg

2

DNS Names

0

Email Addresses

0

IP Addresses

Advanced Certificate Properties

Tehnical certificate details for link.bg

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

link.bg
www.link.bg

Other certificates including the domain name link.bg

(limited to 100 certificates)

Certificate

The complete raw certificate details for link.bg in PEM and ASN.1 format.

Certificate (PEM)

-----BEGIN CERTIFICATE-----
MIIGVDCCBTygAwIBAgISAzr4nkPNiowI6vINrvpLdMVNMA0GCSqGSIb3DQEBCwUA
MEoxCzAJBgNVBAYTAlVTMRYwFAYDVQQKEw1MZXQncyBFbmNyeXB0MSMwIQYDVQQD
ExpMZXQncyBFbmNyeXB0IEF1dGhvcml0eSBYMzAeFw0xODExMTUwMDE1MjBaFw0x
OTAyMTMwMDE1MjBaMBIxEDAOBgNVBAMTB2xpbmsuYmcwggIiMA0GCSqGSIb3DQEB
AQUAA4ICDwAwggIKAoICAQDOJF9lxXRbExUoC7+PIDjOndu62aVWAMnF7yHf7YzI
HtiEWVoGszz4zugWe95dentStuO1iECxnqE2y6rYsuq10FTIFsyaDqgVLsbDJjKp
6FdrVuH5WHmUWcXUxlsVdwk6OUwSHUkCxg1JW6mKqWuL2zPjEHzFUzvuSWkuHEp1
w/Pw7PRXNmltArIijoSXYoi2dY/xQ+cP7xdpO7EijPgMJTtT2UF0XK8eR1aZuoJF
q6vZSG7AM86+9gh6xjnlykXOvO2enxCevTlcJSjdEYufNYiv0HZe03DDUtXzAVVb
xhABM+84ywuGzy0Saxm9aXFqN8fx0cWQ969O2HkQzG8MtbXK1Cdy4WEZzKYATVbZ
GOaaLMqBz1fYXs+zUATvghi5NJN1zZK5Kk8US1+IJCrDJCxJxotobTR2f6PuInBm
m3JKcPX3mWzgkxsEBEWOJUUUFIkFL2q6Do9CJuNgds/kpusNS2iPQ427s7HZSc33
sZVeUjQQ6BLbRNBkzxUcCmg3SvnQIpHxzsnb/VsAT50n54QhOmMtlmBetDZ4oRwd
1jhWYUfBm/XCTFVjKgvqNY6fiANfBeD7po6t2maKEl7aCwXsvpFsXISPFI5NbohQ
sf1A1rBq3bQmU0I1WJ6mC8Bfbo8cceKYGYdwydsjWOtEzi9ufDp52Bb1MxjqCkkd
EwIDAQABo4ICajCCAmYwDgYDVR0PAQH/BAQDAgWgMB0GA1UdJQQWMBQGCCsGAQUF
BwMBBggrBgEFBQcDAjAMBgNVHRMBAf8EAjAAMB0GA1UdDgQWBBTApm7vTds9obOY
MvQ9pp9/XB90RjAfBgNVHSMEGDAWgBSoSmpjBH3duubRObemRWXv86jsoTBvBggr
BgEFBQcBAQRjMGEwLgYIKwYBBQUHMAGGImh0dHA6Ly9vY3NwLmludC14My5sZXRz
ZW5jcnlwdC5vcmcwLwYIKwYBBQUHMAKGI2h0dHA6Ly9jZXJ0LmludC14My5sZXRz
ZW5jcnlwdC5vcmcvMB8GA1UdEQQYMBaCB2xpbmsuYmeCC3d3dy5saW5rLmJnMEwG
A1UdIARFMEMwCAYGZ4EMAQIBMDcGCysGAQQBgt8TAQEBMCgwJgYIKwYBBQUHAgEW
Gmh0dHA6Ly9jcHMubGV0c2VuY3J5cHQub3JnMIIBBQYKKwYBBAHWeQIEAgSB9gSB
8wDxAHcA4mlLribo6UAJ6IYbtjuD1D7n/nSI+6SPKJMBnd3x2/4AAAFnFO/YJAAA
BAMASDBGAiEAoxVqzxU/inQlzTSKhy3alx1KUm87aRWkMe7IVXsoPxcCIQDfznql
hgOyptjs5MedHMvTMb/J2VxCMoC6bmMOC7W4MgB2ACk8UZZUyDlluqpQ/FgH1Ldv
v1h6KXLcpMMM9OVFR/R4AAABZxTv1FEAAAQDAEcwRQIgV1xLl0lC6EU4jxoqt+ih
f1z1hUQricZ0BO3+4j6Sp1kCIQD+n4wU7k2rnPwW7G06XsAWiE82L3Gf9lDGFLJp
bW4qjjANBgkqhkiG9w0BAQsFAAOCAQEAWRhhSAhjeAmaUFMqC4jC3h5GcC5RXPy+
bwfVOygknqc7jH2ZToAfIMYIifkCKm9JoYUmEAMJSSFfWMu5tdpZFYi2aef6FDby
IYNF7IcHe5F9khvsU7Dzpv/bDmaBl/Xtru787OFGRfvGgKfJHsf+b9u7H+btpRqx
rA+yQpLm1El2CS+rJ/xwSyQMEi3dPr1JyyMw08jAAWHFA2sV5x5SzrWpDOLP0CCy
cZqwzF1uyo07KkiIw2x+LllXka60GKICJv+P6UgiySwgdWcaAlOaFE2GVrVsLkNg
v6FptJoTPwZ5iA8s/OshXWMHNbYCdlT/BF3/TgvjvDTp6PFCexm8Kw==
-----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 281403705377759573443161988752248013112653
 . . . . . . . . [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 2018-11-15 00:15:20 +0000 UTC
 . . . . . . . . . . . . [c:0|t:23|false] UTCTime 2019-02-13 00:15:20 +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 'link.bg'
 . . . . . . . . [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 840986316497193112368078200834198824438349353710844084683034783115288356586565703518773344501969984970456190085062798592231016214669865334075375711342572128952862257285220081407261200222005719533712360839186518949024963450571166853342821287769458171319520106520271558090609812981990058921223452307005331311876127461229800779686930561815495413733523334507888786570802165806775417744374163206509456577709214429720820582174926933254293417281005324446855514036969595975807322674242277202710429502403053058999730128084033309087484460068777469311346760780339071909754628634016744066809305271018314006414755746827364238714402509191952488492061316363023722094751048358528570784816985852660063639860544385345267427311697878665723015766175916100822264618923922005191625550379517756682059115819268730614001240060139016915635781777851709819627250046919073747825943469347855612228585366644826193143823408109071557440456621075110689836909566731184084416064617132160421450468079358888452103602402963972148969909288421220983744114246500164472315151018998134518279214293035204450026942856496178529897001286770999355704474567595766128193760635310632842309167513696665355326446131446737342217204111578196130623087866592871438416052023423166267643206931
 . . . . . . . . . . . . . . . . . . . . [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)
							c0a66eef4ddb3da1b39832f43da69f7f5c1f7446
 . . . . . . . . . . . . . . . . [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 (24 bytes)
 . . . . . . . . . . . . . . . . . . . . . . . . [c:0|t:16|true] SEQUENCE, SEQUENCE OF 
 . . . . . . . . . . . . . . . . . . . . . . . . . . . . [c:2|t:2|false] IA5String 'link.bg'
 . . . . . . . . . . . . . . . . . . . . . . . . . . . . [c:2|t:2|false] IA5String 'www.link.bg'
 . . . . . . . . . . . . . . . . [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)
							00f1007700e2694bae26e8e94009e8861bb63b83d43ee7fe7488fba48f2893019dddf1dbfe0000016714efd8240000040300483046022100a3156acf153f8a7425cd348a872dda971d4a526f3b6915a431eec8557b283f17022100dfce7aa58603b2a6d8ece4c79d1ccbd331bfc9d95c423280ba6e630e0bb5b832007600293c519654c83965baaa50fc5807d4b76fbf587a2972dca4c30cf4e54547f4780000016714efd45100000403004730450220575c4b974942e845388f1a2ab7e8a17f5cf585442b89c67404edfee23e92a759022100fe9f8c14ee4dab9cfc16ec6d3a5ec016884f362f719ff650c614b2696d6e2a8e
 . . . . [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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