univ-nantes.fr

Checked 22 October 2026, 05:36 UTC · via 8.8.8.8
✗Problems found
21 passed 6 warnings 2 failed 2 info

SPF

warn

SPF record published

Found

Record
v=spf1 include:spf0.univ-nantes.fr include:spf.brevo.com ?all
DNS lookups
8 of 10
Void lookups
0 of 2

Checks

  • ✓ No deprecated ptr mechanism #1
    No ptr mechanism found in SPF record.
  • ✓ 8 of 10 DNS lookups #2
    SPF record needs 8 DNS lookups (limit is 10).
  • !
    Ends with ?all (neutral)
    SPF record uses ?all (neutral), which gives no protection against unauthorized senders. Use -all or ~all instead.
    #3
  • ✓ Record published #6
    SPF record exists for this domain.
  • ✓ Single record #16
    Exactly one SPF record is published.
  • ✓ Valid syntax #25
    All SPF mechanisms and modifiers are valid.
  • ✓ No void lookups #26
    All include/redirect targets exist.
  • ✓ No overly broad IP ranges #27
    All ip4/ip6 ranges are narrow enough.

DMARC

fail

p=none (_dmarc.univ-nantes.fr)

Found

Record
v=DMARC1; p=none; rua=mailto:re+rhxnnh9sytg@dmarc.postmarkapp.com, mailto:dmarc@relay.renater.fr; fo=0; adkim=r; aspf=r; pct=100; rf=afrf; sp=none
Found at
_dmarc.univ-nantes.fr
External report address
mailto:re+rhxnnh9sytg@dmarc.postmarkapp.com (authorized)
External report address
mailto:dmarc@relay.renater.fr (authorized)
TagValueMeaning
vDMARC1Version
pnonePolicy
spnoneSubdomain policy
pct100Percentage of mail the policy applies to
ruamailto:re+rhxnnh9sytg@dmarc.postmarkapp.com, mailto:dmarc@relay.renater.frAggregate report addresses
adkimrDKIM alignment (r = relaxed, s = strict)
aspfrSPF alignment (r = relaxed, s = strict)
fo0Failure reporting options
rfafrfFailure report format

Checks

  • ✗
    Policy: none (monitoring only)
    DMARC policy is set to 'none', which only monitors but doesn't protect against spoofing. Consider upgrading to 'quarantine' or ideally 'reject'.
    #4
  • ✓ Record published #5
    DMARC record exists for this domain.
  • ✓ Valid syntax #17
    DMARC record syntax is valid.
  • ✓ Aggregate reports enabled #19
    Aggregate reports are sent to: mailto:re+rhxnnh9sytg@dmarc.postmarkapp.com, mailto:dmarc@relay.renater.fr
  • ✓ External report addresses authorized #29
    Report addresses in other domains have published their authorization.

DKIM

warn

Selectors: mail, mta

Found

Selectors
mail, mta
_domainkey
NOERROR
SelectorKeyFlags
mailRSA 1024 bits
mtaRSA 1024 bits

Checks

  • ✓ Keys found: mail, mta #7
    DKIM keys found for this domain with selectors: mail, mta
  • !
    1024-bit DKIM key
    1024-bit RSA keys are the minimum and are considered weak today: mail (1024 bits), mta (1024 bits). Rotate to a 2048-bit key.
    #23
  • ✓ No problematic flags #24
    No keys in test mode, revoked, or limited to SHA-1.

DNSSEC

warn

Not signed

Found

DNSKEY records
No (0)
DS at parent
No

Checks

  • !
    Not enabled
    DNSSEC is not enabled for this domain. Consider enabling DNSSEC to protect against DNS spoofing attacks.
    #8

MX

warn

2 mail servers

Found

PriorityHostRecordsReverse DNS
10mx1.relay.renater.frA 85.31.212.3mx1.relay.renater.fr ✓
10mx2.relay.renater.frA 85.31.212.203mx2.relay.renater.fr ✓

Checks

  • ✓ 2 MX records #9
    Found 2 MX records for this domain.
  • ✓ All hosts resolve #10
    All MX records resolve to valid IP addresses.
  • !
    Hosts without IPv6
    The following MX hosts could not be resolved to IPv6 addresses: mx1.relay.renater.fr, mx2.relay.renater.fr
    #11
  • ✓ Redundant MX hosts #12
    Found 2 MX records, which provides redundancy for email delivery.
  • ✓ At most 5 MX records #13
    Found 2 MX records, which is within the recommended range (1-5).
  • ✓ No localhost targets #14
    No MX records pointing to localhost found.
  • ✓ No private IP addresses #15
    No MX records resolving to private IP addresses found.
  • ✓ No CNAME targets #22
    No MX records point to a CNAME.
  • ✓ Reverse DNS confirmed #30
    All 2 MX addresss have a PTR record that resolves back to them.

TLS

warn

no MTA-STS · no TLS-RPT · DANE on 0 of 2 MX hosts

Found

DANE (TLSA records)

MX hostTLSADNSSEC
mx1.relay.renater.frnone-
mx2.relay.renater.frnone-

Checks

  • !
    Not configured
    MTA-STS is not configured, so other mail servers fall back to unencrypted delivery when TLS fails or is stripped by an attacker. Publish a _mta-sts TXT record and a policy at https://mta-sts.<domain>/.well-known/mta-sts.txt.
    #32
  • i
    Not configured
    TLS-RPT lets senders report TLS delivery problems to you. It is most useful together with MTA-STS or DANE.
    #35
  • i
    Not used
    No MX host publishes TLSA records. DANE lets senders verify your mail server's certificate through DNSSEC; it requires DNSSEC on the MX host's zone.
    #36

BIMI

fail

https://cdn.univ-nantes.fr/images/bimi-logo-nu.svg

Found

Record
v=BIMI1; l=https://cdn.univ-nantes.fr/images/bimi-logo-nu.svg
Found at
default._bimi.univ-nantes.fr
Logo
https://cdn.univ-nantes.fr/images/bimi-logo-nu.svg

Checks

  • !
    No certificate (a=)
    The logo is published without a Verified Mark Certificate. Gmail and Apple Mail only show BIMI logos with a VMC or CMC; Yahoo shows it without one.
    #38
  • ✗
    DMARC not strict enough for BIMI
    Mail clients will not show the logo. BIMI requires DMARC p=quarantine or p=reject (now p=none), a subdomain policy other than sp=none.
    #39