smtp.cus.org

Issued by Let's Encrypt Authority X3

About this certificate

This digital certificate with serial number 04:c1:10:85:b0:dd:88:f8:9d:f6:75:4a:8c:e9:1e:4e:fe:38 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=smtp.cus.org

Let's Encrypt

Organization: Let's Encrypt
Country: US

This certificate has expire since

Certificate Details

Serial Number (hex): 04:c1:10:85:b0:dd:88:f8:9d:f6:75:4a:8c:e9:1e:4e:fe:38
Serial Number (int): 414145602353452758500211221868959948013112
Serial Number lenght: 139 bits, 18 octets

SubjectKeyId: 22:19:dc:df:8b:30:65:62:6e:03:bd:8d:87:e6:52:ff:7b:39:31:e5
AuthorityKeyId: a8:4a:6a:63:04:7d:dd:ba:e6:d1:39:b7:a6:45:65:ef:f3:a8:ec:a1

Fingerprint (sha1): 56:8f:bd:91:83:e3:4f:34:0d:72:39:47:1b:44:fe:f1:0c:1c:30:a5
Fingerprint (sha256): 59:e9:be:e7:a8:b0:26:7f:39:c5:ea:ad:e5:ff:95:d4:e3:e0:6e:3a:17:aa:73:73:63:da:87:e3:c7:30:ab:00

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 smtp.cus.org

2

DNS Names

0

Email Addresses

0

IP Addresses

Advanced Certificate Properties

Tehnical certificate details for smtp.cus.org

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

smtp.cus.org
smtp.cus.societies.cam.ac.uk

Other certificates including the domain name cus.org

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cus.org
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cus.org
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www.hawkingfellowship.cus.org
bar.cus.org
cus.org
smtp.cus.org
hire.cus.org
hire.cus.org
smtp.cus.org
bar.cus.org
cus.org
hire.cus.org
hire.cus.org
hire.cus.org
hire.cus.org
exch1.cus.org
hire.cus.org
hire.cus.org
hire.cus.org
hire.cus.org
bar.cus.org
cus.org
admin.cus.org
cus.org
cus.org
bar.cus.org
bar.cus.org
hire.cus.org
bar.cus.org
bar.cus.org
hire.cus.org
smtp.cus.org
cus.org
hire.cus.org
bar.cus.org
exch1.cus.org
bar.cus.org
hire.cus.org
smtp.cus.org
hire.cus.org
hire.cus.org
hire.cus.org
smtp.cus.org
hire.cus.org
hire.cus.org
hire.cus.org
hire.cus.org
cus.org
unifi.cus.org
smtp.cus.org
hire.cus.org
hire.cus.org
exch1.cus.org
www.cus.org
exch1.cus.org
bar.cus.org
hire.cus.org
sharepoint.cus.org
cus.org
unifi.cus.org
bar.cus.org
bar.cus.org
smtp.cus.org
www.cus.org
exch1.cus.org
hire.cus.org
officewebapps.cus.org
hire.cus.org
hire.cus.org
smtp.cus.org
hire.cus.org
hire.cus.org
hire.cus.org
smtp.cus.org
hire.cus.org
hire.cus.org
cus.org
bar.cus.org
confluence.cus.org
smtp.cus.org
hire.cus.org
cus.org
cus.org
cus.org
cus.org
bar.cus.org
hire.cus.org
smtp.cus.org
cus.org
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avayavc.cus.org
hire.cus.org
smtp.cus.org
hire.cus.org
hire.cus.org
mail.cus.org

Certificate

The complete raw certificate details for smtp.cus.org in PEM and ASN.1 format.

Certificate (PEM)

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

Public Key (PEM)

-----BEGIN PUBLIC KEY-----
MIIBIjANBgkqhkiG9w0BAQEFAAOCAQ8AMIIBCgKCAQEAyYjkq81dbqrCnzY+oNfZ
1TPvUrhy+7+wCJ+z34pl9Folp3wTDmyAVOyx0KBAHg1aJiGmfQfwXtICZjSDi4xG
8G8oV0H4f1HZGLM/q7GfkokSq5XECKh9BWHHkUDfSk2fn2iiXEKwcMtUXov3EnHH
BqX5te0F6elJtIOxZrBr7YilVLQuMBI/hIbKXSmf8qyNt+PhUpvg9WAUj5rhfQUR
UZdI5cZ0XrSK9loR4uGU2PCwaKUleP3NHGLNlD3pr84LufnnZq3jFCHzloxE0Y8L
ko4N+Bc8KOs3I+XiI0LZAIFWVTQZsHrcsdMd8UCsJS0ttzQqhX0LH5/BvGPicbgb
GQIDAQAB
-----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 414145602353452758500211221868959948013112
 . . . . . . . . [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 2018-12-31 23:27:49 +0000 UTC
 . . . . . . . . . . . . [c:0|t:23|false] UTCTime 2019-03-31 23:27:49 +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 'smtp.cus.org'
 . . . . . . . . [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 25441403873953788650854615601122987890960429530579245351487229612557264122485336994729682284125241153846167505457454283216725717240655762258194289904655211013453477603224024912807899042275829333389573088741531335404769087835244046071437286460563898390576730873775766505777578793386869328528091793085081283474295041351862863855498436922346154295072553412031795114161197436080873658315043625252354682924856030209340679752217149361892703280428601480036708647797300839245301464463662983871358218788218328426789499296063968251020251742843043496897068709582497062647381716964730132261587195533780018333236864513093897034521
 . . . . . . . . . . . . . . . . . . . . [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)
							2219dcdf8b3065626e03bd8d87e652ff7b3931e5
 . . . . . . . . . . . . . . . . [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 (46 bytes)
 . . . . . . . . . . . . . . . . . . . . . . . . [c:0|t:16|true] SEQUENCE, SEQUENCE OF 
 . . . . . . . . . . . . . . . . . . . . . . . . . . . . [c:2|t:2|false] IA5String 'smtp.cus.org'
 . . . . . . . . . . . . . . . . . . . . . . . . . . . . [c:2|t:2|false] IA5String 'smtp.cus.societies.cam.ac.uk'
 . . . . . . . . . . . . . . . . [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 (245 bytes)
 . . . . . . . . . . . . . . . . . . . . . . . . [c:0|t:4|false] OCTET STRING (242 bytes)
							00f00076005581d4c2169036014aea0b9b573c53f0c0e43878702508172fa3aa1d0713d30c0000016806cf373e00000403004730450221008c13c55b5639c3ba1d278b2515153793f68d1771e1d580bfdfcabf5d31880f99022072bdbb4806f60d94d29473649c4e6a370d0f5634d3e49d5a211b31b2129638cb00760063f2dbcde83bcc2ccf0b728427576b33a48d61778fbd75a638b1c768544bd88d0000016806cf38c40000040300473045022100c7ffc4f5913a64f66aa74474da850ecdb865e1e0a62111a5c1758f463c34755902201507c6873f9e8ff802038b63fa29aa9daebfe04f84da08de8a592fc79893d75d
 . . . . [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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