
Engineer's DNS Intelligence Report
This domain publishes a Null MX record (RFC 7505) but lacks a DMARC reject policy. Without it, attackers can still spoof email from this domain. Complete the no-mail hardening with a strict DMARC reject policy.
| Field | Value |
|---|---|
| Type | TXT |
| Host | _dmarc.swutch.com |
| Value | v=DMARC1; p=reject; sp=reject; adkim=s; aspf=s; |
DNSSEC is not enabled for this domain. DNSSEC provides cryptographic authentication of DNS responses, preventing cache poisoning and DNS spoofing attacks.
CAA records specify which Certificate Authorities may issue certificates for your domain, reducing the risk of unauthorized certificate issuance.
| Field | Value |
|---|---|
| Type | CAA |
| Host | swutch.com (root of domain — adjust CA to match your provider) |
| Value | 0 issue "letsencrypt.org" |
Email Security Methodology Can this domain be impersonated by email? No null MX indicates no-mail domain
SPF Record RFC 7208 §4 Gold
Valid SPF (no mail allowed) - domain declares it sends no email
DMARC Policy RFC 7489 §6.3 Gold
No valid DMARC record found
pct= with t= (testing flag), add np= (non-existent subdomain policy), and mandate DNS tree walk for policy discovery instead of the Public Suffix List.DKIM Records RFC 6376 §3.6 Gold
DKIM not discoverable via common selectors (large providers use rotating selectors)
_domainkey.swutch.com NS records point to
an external service
(ns1.afternic.com, ns2.afternic.com).
DKIM selectors are dynamically managed and may include keys for services beyond what static scanning discovers.
l= tag body length vulnerability (attacker appends unsigned content to signed mail),
weak key exploitation (keys below 1024-bit are cryptographically breakable per RFC 6376 §3.3.3),
DKIM replay attacks (re-sending legitimately signed messages at scale)
MTA-STS RFC 8461 §3 Gold
No valid MTA-STS record found
MTA-STS policy enforcement is evaluated in Mail Transport Security below.
TLS-RPT RFC 8460 §3 Gold
No valid TLS-RPT record found
The following DNS record TTLs deviate from recommended values. Incorrect TTLs can cause caching issues, slow propagation, or unnecessary DNS traffic.
| Record Type | Observed TTL | Typical TTL | Severity | Context |
|---|---|---|---|---|
| NS | 6 hours (21600s) |
1 day (86400s) |
medium | NS TTL is below typical — observed 6 hours (21600s), typical value is 1 day (86400s). Short TTLs increase DNS query volume but enable faster propagation. If you are preparing for a migration or need rapid failover, this may be intentional (RFC 1035 §3.2.1). For steady-state production, consider 86400 seconds per NIST SP 800-53 SI-7 relevance guidance. Use the TTL Tuner for profile-specific recommendations. |
Big Picture Questions
- How often do you actually change this record? If it hasn’t changed in months, a short TTL is generating unnecessary DNS queries without any benefit.
- Are you preparing for a migration or IP change? Short TTLs make sense temporarily — but should be raised back to 1 hour (3600s) once the change is complete.
- Every DNS lookup adds 20–150ms of latency. With a 60s TTL, returning visitors trigger a fresh lookup every minute. With 3600s, they get cached responses for an hour — faster page loads, no extra infrastructure needed.
- Google runs A records at ~30s because they operate a global anycast network and need to steer traffic dynamically. For a typical website without that infrastructure, copying those TTLs increases query volume with zero upside.
ns2.afternic.com
1
dns.jomax.net
| Timer | Value | RFC 1912 Range |
|---|---|---|
| Refresh | 28800s | 1,200–43,200s (20 min – 12 hrs) |
| Retry | 7200s | Fraction of Refresh |
| Expire | 604800s | 1,209,600–2,419,200s (14–28 days) |
| Minimum (Neg. Cache) | 86400s | 300–86,400s (5 min – 1 day) |
