Identity
97
B
runbox.com
Posture Score: 84/100
Scanned May 10, 2026 at 5:50 AM UTC
Score History
Attack Surface
70
Reputation
84
Identity Findings
Single MX record — no redundancy
Only one MX record exists. If this mail server goes down, all inbound mail will bounce. Most production mail systems use 2+ MX records with different priorities.
💡 Add a secondary MX record with a higher priority number (e.g., priority 20) pointing to a backup mail server.
MTA-STS is in testing mode
The MTA-STS policy is in testing mode and not actively enforcing TLS.
💡 Switch mode to "enforce" once TLS is confirmed working for all MX hosts.
ARC support not detected
No evidence of ARC (Authenticated Received Chain) support on MX servers. Forwarded messages may lose authentication.
💡 Consider enabling ARC signing on your mail servers to preserve authentication through forwarding.
SPF record is valid
The SPF record is properly configured with valid syntax and within lookup limits.
SPF record length OK (34 bytes)
SPF record is within safe DNS packet size limits.
DKIM records are valid
DKIM records found and validated for selectors: selector1, selector2
DKIM cryptographic configuration is compliant
No RFC 8301 compliance issues detected in DKIM key configuration.
DKIM key strength indicates modern key management
All DKIM keys use RSA-2048+ or Ed25519, consistent with current best practices.
No external DMARC report destinations
All DMARC report URIs point to the same domain — no external authorization needed.
Subdomains protected (sp=quarantine)
DMARC subdomain policy enforces quarantine or reject on unauthenticated subdomain mail.
MX records are valid
All MX records are properly configured.
TLS-RPT report destinations are reachable
All TLS-RPT rua= URIs point to resolvable domains.
Meets bulk sender authentication requirements
Domain has SPF, DKIM, and DMARC — meeting Google/Yahoo 2024 bulk sender requirements for email authentication.
SMTP security checks passed
No open relay, VRFY/EXPN, or banner disclosure issues detected.
SMTP RFC 5321 compliance checks passed
The mail server accepts postmaster@ and abuse@ and uses a valid FQDN in EHLO.
IPv6 readiness is good
IPv6 records are present and properly configured.
STARTTLS downgrade resistance is adequate
STARTTLS is supported with modern TLS and protected by MTA-STS and/or DANE.
NS delegation is properly configured
All nameservers are responsive, consistent, and properly secured.
DNS responses are consistent across all nameservers
All authoritative nameservers return consistent answers with proper AA flags.
DNS TTL values follow best practices
All critical DNS record TTLs are within recommended ranges.
DKIM2 not detected
No DKIM key record with v=2 was found across common selectors. DKIM2 is an emerging standard and not yet widely deployed.
DMARC alignment: adkim=r, aspf=r
DKIM alignment is relaxed, SPF alignment is relaxed.
DMARCbis np tag absent
The DMARC record does not include the np (non-existent subdomain policy) tag. Consider adding np=reject to protect non-existent subdomains under DMARCbis.
Deprecated DMARCbis tags found: pct
The DMARC record contains tags deprecated in DMARCbis: pct. Consider removing these for forward compatibility.
DMARCbis psd tag absent
The DMARC record does not include the psd (public suffix domain) indicator. Consider adding psd=n to explicitly identify this as an organizational domain.
REQUIRETLS not advertised
The primary MX does not advertise REQUIRETLS (RFC 8689). This is an emerging standard — MTA-STS and DANE provide adequate TLS enforcement for most deployments.
DANE/TLSA configured for mx.runbox.com
TLSA records found and TLS certificate is available for verification.
No BIMI record found
BIMI is not configured. Your brand logo will not display in supporting email clients.
Open mail ports on mx.runbox.com
Detected open mail-related ports: 25, 110, 143, 465, 587, 993, 995
RFC 8058 one-click unsubscribe assessment
DKIM signing is configured. RFC 8058 compliance depends on List-Unsubscribe and List-Unsubscribe-Post headers being included in outbound messages and DKIM signatures.
MX IP network diversity
All MX IPs are in the same /16 network. Consider diversifying across networks for resilience.
SOA record parameters
Serial: 3000010843, Refresh: 14400s, Retry: 3600s, Expire: 1296000s, Min TTL: 3600s
Authorized certificate authorities
CAA records restrict certificate issuance to: buypass.no, letsencrypt.org
Attack Surface Findings
NSEC records enable zone walking
The domain uses NSEC records for DNSSEC authenticated denial of existence. NSEC records can be walked to enumerate all names in the zone, effectively disclosing the entire zone contents.
💡 Switch from NSEC to NSEC3 with opt-out to prevent zone enumeration. Use NSEC3 with a random salt and sufficient iterations.
Domain enumerability: high
The domain is highly enumerable. Zone transfers, NSEC zone walking, or a combination of factors make it easy to discover all DNS records.
💡 Restrict zone transfers, use NSEC3 instead of NSEC, consider wildcard certificates to reduce CT log exposure, and implement rate limiting on DNS queries.
Microsoft Autodiscover accessible without authentication
The Autodiscover endpoint at https://autodiscover.runbox.com/autodiscover/autodiscover.xml returns configuration data without requiring authentication. This exposes email server details to unauthenticated users.
💡 Configure the Autodiscover endpoint to require authentication before returning configuration data.
NSEC used instead of NSEC3 (zone enumeration possible)
The domain uses NSEC records for authenticated denial of existence. NSEC allows zone walking.
💡 Migrate from NSEC to NSEC3 to prevent zone enumeration.
DNS ANY query returns 1 record(s)
The DNS server responds to ANY queries with 1 record(s). The low record count limits amplification risk, but ANY responses still aid reconnaissance.
💡 Configure the DNS server to refuse or minimize ANY query responses per RFC 8482.
Mozilla Autoconfig endpoint detected
The Autoconfig endpoint at autoconfig.runbox.com is publicly accessible and exposes mail server configuration details.
💡 Review the autoconfig XML to ensure it does not expose internal server names or sensitive configuration.
All MX records resolve correctly
No dangling MX records detected — all MX hostnames resolve to valid IP addresses.
Explicit MX records present
The domain has explicit MX records — no implicit A-record fallback delivery.
No internal information leakage detected
No non-routable IP addresses or internal references were found in public DNS records.
13 subdomain(s) discovered for runbox.com
Subdomains were enumerated via Certificate Transparency logs, DNS wordlist brute-forcing, and DNS record analysis.
0 certificate(s) found in CT logs
Certificate Transparency logs contain 0 certificate(s) for runbox.com and its subdomains. Each certificate reveals subdomain names.
Wildcard DNS record detected
A wildcard DNS record exists for *.runbox.com, resolving to 185.226.149.25. Wildcard records make subdomain brute-forcing less effective but may mask misconfigurations.
1 email SRV record(s) found
Email service SRV records expose mail server configuration for automatic client setup.
DNSSEC is enabled
DNSKEY and/or DS records are present, indicating DNSSEC is configured.
Reputation Findings
TLS certificate expires in 16 days
Certificate for runbox.com expires on 2026-05-26 (16 days).
💡 Renew the TLS certificate soon — it expires within 30 days.
Missing domain locks: clientDeleteProhibited
Domain runbox.com is missing protective locks: clientDeleteProhibited.
💡 Enable clientTransferProhibited and clientDeleteProhibited locks through your registrar to prevent unauthorized transfers or deletions.
HSTS enabled with preload on runbox.com
Strict-Transport-Security: max-age=63072000; preload
HSTS enabled with preload on webmail.runbox.com
Strict-Transport-Security: max-age=63072000; preload
security.txt present
Found security.txt at https://runbox.com/.well-known/security.txt.
Certificate issued by Buypass Class 3 CA 2
The certificate for runbox.com is issued by a third-party CA.
Signature algorithm: rsa-sha256
The certificate for runbox.com uses an acceptable signature algorithm.
RSA key: 4096 bits
The certificate for runbox.com uses an adequate RSA key of 4096 bits.
SCTs present in certificate
The certificate for runbox.com contains Signed Certificate Timestamps.
No weak ciphers detected
No known weak cipher suites detected on runbox.com.
Domain valid for 92 days
Domain runbox.com expires on 2026-08-10.
TLD has good reputation
The .com TLD is not on known abuse watchlists.
DMARC reporting destinations look legitimate
DMARC rua/ruf addresses do not point to known URL shortener services.
MX records point to stable infrastructure
No MX records point to known dynamic DNS service domains.
Strong TLS configuration on primary MX
Primary MX (mx.runbox.com) uses TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 including Forward Secrecy.
SMTP banner matches infrastructure identity
The SMTP banner (aibo.runbox.com) aligns with the MX hostname (mx.runbox.com).
Google Safe Browsing DNS check — no flag detected
DNS-based Safe Browsing lookup returned no results. Full verification requires the Google Safe Browsing API key.
Abuse contact lookup failed
Could not query abuse contact information.
PhishTank — API key required
PhishTank phishing database check requires an API key.
Sender Score — API key required
Sender Score reputation check requires an API key.
Cisco Talos — API key required
Cisco Talos IP reputation check requires an API key.
WHOIS registration data
Registrar: eNom, LLC | Created: 1999-08-10 | Expires: 2026-08-10 | Updated: 2025-07-12
WHOIS privacy protection enabled
Domain runbox.com has WHOIS privacy/redaction enabled.
Typosquat detected: rnbox.com (has MX!), runobx.com (has MX!), tunbox.com (has MX!), funbox.com (has MX!), rinbox.com (has MX!)
17 registered lookalike domain(s) that could be used for phishing against your brand. Showing top 5 of 17. Domains with MX records can send and receive email, making them high-risk phishing vectors.
Dependency Chains
DMARC Authentication Chain (SPF)
DMARC uses SPF to verify that emails come from authorized servers
SPF Record
SPF record found and configured
→
DMARC Policy
DMARC policy: quarantine
DMARC Authentication Chain (DKIM)
DMARC uses DKIM to verify that emails have not been tampered with
DKIM Signature
DKIM signature missing
→
DMARC Policy
DMARC policy: quarantine
⚠️ DKIM signature is missing. DMARC relies on DKIM to verify email integrity and prevent tampering. Without DKIM, DMARC alignment will fail for cryptographic verification.
Mail Server Identity: mx.runbox.com
PTR record proves mail server legitimacy
MX: mx.runbox.com
Mail server at 185.226.149.25
→
PTR Record
Reverse DNS: aibo.runbox.com
Mail Server Reputation: mx.runbox.com
RBL check ensures server is not blacklisted
MX: mx.runbox.com
Mail server at 185.226.149.25
→
RBL Status
Not blacklisted
Enforced Encryption Chain
MTA-STS enforces TLS encryption to prevent man-in-the-middle attacks
TLS Support
Mail servers support TLS encryption
→
MTA-STS Policy
Mode: testing
Brand Identity Chain
BIMI displays your logo in email clients, but requires DMARC enforcement
DMARC Enforcement
DMARC policy: quarantine
→
BIMI Record
BIMI not configured
⚠️ BIMI record is missing. Even with DMARC enforcement, you need to configure BIMI to display your brand logo in supported email clients.
TLS Monitoring Chain
TLS-RPT provides reports about TLS connection failures
TLS Support
Mail servers support TLS encryption
→
TLS-RPT Reporting
TLS failure reporting configured
Security Checks
MX Records
✓
SPF Record
✓
DKIM Record
✗
DMARC Policy
✓
BIMI Record
✗
CAA Records
✓
DNSSEC
✓
MTA-STS
✓
TLS-RPT
✓
Embed Badge
Display your domain's security grade on your website or README:
<img src="https://scan.ractermx.com/badge/runbox.com.svg" alt="Email Security Grade">
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