SSL-Tools

SSL check results of seaborgium.cferr.fr

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Discover if the mail servers for seaborgium.cferr.fr can be reached through a secure connection.

To establish a secure connection a mail server has to offer STARTTLS (SSL), a trustworthy SSL certificate, support for the Diffie-Hellman-Algorithm to guarantee Perfect Forward Secrecy and must not be vulnerable against the Heartbleed attack. Futhermore we recommend using end-to-end encryption with GnuPG.

Summary

JSON Refresh

Report created Sun, 26 Apr 2026 00:30:25 +0000

The mailservers of seaborgium.cferr.fr can be reached through a secure connection.

Servers

Incoming Mails

These servers are responsible for incoming mails to @seaborgium.cferr.fr addresses.

Hostname / IP address Priority STARTTLS Certificates Protocol
seaborgium.cferr.fr
51.255.168.195
 -
supported
cferr.fr
DANE
valid
PFS
supported
Heartbleed
not vulnerable
Weak ciphers
not found
  • TLSv1.2
  • TLSv1.1
  • TLSv1.0
  • SSLv3
4 s
seaborgium.cferr.fr
2001:41d0:401:3100::6f8e
 -
supported
cferr.fr
DANE
valid
PFS
supported
Heartbleed
not vulnerable
Weak ciphers
not found
  • TLSv1.2
  • TLSv1.1
  • TLSv1.0
  • SSLv3
3 s

Outgoing Mails

We have not received any emails from a @seaborgium.cferr.fr address so far. Test mail delivery

Certificates

First seen at:

CN=cferr.fr

Certificate chain
  • cferr.fr
    • remaining
    • 2048 bit
    • sha256WithRSAEncryption
      • R12
        • remaining
        • 2048 bit
        • sha256WithRSAEncryption
          • ISRG Root X1 (Certificate is self-signed.)
            • remaining
            • 4096 bit
            • sha256WithRSAEncryption
Subject
Common Name (CN)
  • cferr.fr
Alternative Names
  • cferr.fr
  • courrier.cferr.fr
  • seaborgium.cferr.fr
  • seaborgium.internal.sbg.cferr.fr
Issuer
Country (C)
  • US
Organization (O)
  • Let's Encrypt
Common Name (CN)
  • R12
validity period
Not valid before
2026-03-27
Not valid after
2026-06-25
This certifcate has been verified for the following usages:
  • Digital Signature
  • Key Encipherment
  • TLS Web Server Authentication
Fingerprints
SHA256
4D:D7:BC:5F:B5:04:1A:CD:1E:92:66:3B:E4:49:9F:BE:0F:97:56:77:4C:4B:AF:F3:33:15:E0:9A:12:77:A3:57
SHA1
0A:1F:2F:23:ED:C6:64:72:E4:56:4F:9F:E6:3C:76:5A:E0:4B:CC:63
X509v3 extensions
subjectKeyIdentifier
  • 6F:95:73:14:B4:8F:76:C0:BC:93:AE:97:B3:58:51:16:4F:D4:7F:14
authorityKeyIdentifier
  • keyid:00:B5:29:F2:2D:8E:6F:31:E8:9B:4C:AD:78:3E:FA:DC:E9:0C:D1:D2
authorityInfoAccess
  • CA Issuers - URI:http://r12.i.lencr.org/
certificatePolicies
  • Policy: 2.23.140.1.2.1
crlDistributionPoints
  • Full Name:
  • URI:http://r12.c.lencr.org/39.crl
ct_precert_scts
  • Signed Certificate Timestamp:
  • Version : v1 (0x0)
  • Log ID : 64:11:C4:6C:A4:12:EC:A7:89:1C:A2:02:2E:00:BC:AB:
  • 4F:28:07:D4:1E:35:27:AB:EA:FE:D5:03:C9:7D:CD:F0
  • Timestamp : Mar 27 13:54:05.191 2026 GMT
  • Extensions: none
  • Signature : ecdsa-with-SHA256
  • 30:45:02:21:00:B9:48:38:90:79:92:D0:74:62:46:0E:
  • AA:0A:F2:DD:72:5D:6B:A1:D2:E4:95:D0:4F:D5:72:25:
  • 11:3C:9F:38:67:02:20:3A:3E:33:C0:13:68:5E:23:A2:
  • 37:B9:A6:6E:A3:4B:BC:23:60:61:11:B3:E8:E8:CA:BC:
  • C3:55:49:26:F3:44:FB
  • Signed Certificate Timestamp:
  • Version : v1 (0x0)
  • Log ID : 1A:8B:9D:69:4A:57:98:C8:99:A0:CA:88:BD:F4:8F:C0:
  • B4:56:60:CC:C3:60:0D:1F:71:F4:69:FF:C7:D1:AC:A3
  • Timestamp : Mar 27 13:54:05.283 2026 GMT
  • Extensions: 00:00:05:00:58:E7:B5:3C
  • Signature : ecdsa-with-SHA256
  • 30:45:02:20:26:B6:40:CE:20:24:B3:8D:C7:A3:72:89:
  • D0:FF:89:2B:B4:59:FF:ED:31:8A:61:D8:0F:BD:A2:F8:
  • CC:4E:7E:44:02:21:00:D3:17:69:E0:81:06:AF:41:37:
  • DD:D1:90:77:37:B5:DE:2D:90:61:11:EA:B8:64:F1:4A:
  • 45:F0:CE:15:A1:E3:F9

DANE

DNS-based Authentication of Named Entities (DANE) is a protocol to allow X.509 certificates to be bound to DNS using TLSA records and DNSSEC.

Name Options DNSSEC Matches
_25._tcp.seaborgium.cferr.fr
  • DANE-EE: Domain Issued Certificate
  • Use subject public key
  • SHA-256 Hash
valid
valid