Identity
82
B
citigroup.com
Posture Score: 89/100
Scanned May 9, 2026 at 4:26 AM UTC
Score History
Attack Surface
92
Reputation
92
Identity Findings
No DKIM records found
No DKIM records were found for any common selector. Email may not be authenticated.
💡 Configure DKIM signing and publish the public key at <selector>._domainkey.citigroup.com
No MTA-STS record found
Without MTA-STS, mail transport encryption cannot be enforced and is vulnerable to downgrade attacks.
💡 Publish a _mta-sts TXT record and host a policy file at https://mta-sts.citigroup.com/.well-known/mta-sts.txt
STARTTLS without MTA-STS or DANE protection
STARTTLS alone is vulnerable to downgrade attacks. Neither MTA-STS nor DANE is configured to enforce encryption.
💡 Deploy MTA-STS and/or DANE to protect against STARTTLS stripping attacks.
No TLS-RPT record found
Without TLS-RPT, you will not receive reports about TLS negotiation failures.
💡 Publish a _smtp._tls TXT record (e.g. "v=TLSRPTv1; rua=mailto:tls-reports@citigroup.com").
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 (119 bytes)
SPF record is within safe DNS packet size limits.
DKIM cryptographic configuration is compliant
No RFC 8301 compliance issues detected in DKIM key configuration.
All external report destinations authorized
External DMARC report destinations have valid authorization records per RFC 7489 §7.1.
Subdomains protected (sp=reject)
DMARC subdomain policy enforces quarantine or reject on unauthenticated subdomain mail.
No deprecated DMARCbis tags present
The DMARC record does not use any tags deprecated in DMARCbis (pct, rf, ri).
MX records are valid
All MX records are properly configured.
2 MX records with 2 unique IPs
Multiple MX records provide mail delivery redundancy.
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.
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.
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.
No DANE/TLSA records found
DANE is not configured for any MX server. This is optional but provides strong certificate binding.
No BIMI record found
BIMI is not configured. Your brand logo will not display in supporting email clients.
Open mail ports on mx-a.mail.citi.com
Detected open mail-related ports: 25
Domain is IPv4-only
No AAAA records found for the domain, MX servers, or nameservers. The domain operates on IPv4 only.
RFC 8058 one-click unsubscribe assessment
No DKIM signing detected. RFC 8058 one-click unsubscribe requires DKIM-signed List-Unsubscribe headers.
MX IP network diversity
All MX IPs are in the same /16 network. Consider diversifying across networks for resilience.
SOA record parameters
Serial: 2021103010, Refresh: 3600s, Retry: 300s, Expire: 2419200s, Min TTL: 3600s
Authorized certificate authorities
CAA records restrict certificate issuance to: digicert.com, globalsign.com
Attack Surface Findings
Domain enumerability: medium
The domain has moderate enumerability. CT logs and DNS records reveal significant information about the domain structure.
💡 Restrict zone transfers, use NSEC3 instead of NSEC, consider wildcard certificates to reduce CT log exposure, and implement rate limiting on DNS queries.
DNSSEC is not enabled
No DNSKEY or DS records were found. DNS responses are not cryptographically authenticated.
💡 Enable DNSSEC by generating DNSKEY records and publishing DS records at the registrar.
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.
No excessive DNS information exposure detected
No HINFO, LOC, RP records, version disclosures, or zone walking vulnerabilities were found.
No email autodiscovery endpoints detected
No Microsoft Autodiscover, Mozilla Autoconfig, or email SRV records were found.
3 subdomain(s) discovered for citigroup.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 citigroup.com and its subdomains. Each certificate reveals subdomain names.
Reputation Findings
DMARC reports sent to URL shortener domain
DMARC aggregate or forensic reports contain sensitive authentication metadata. Sending them to URL shortener domains indicates misconfiguration or a compromised record.
💡 Change DMARC rua/ruf addresses to a domain you control.
HSTS enabled with preload on citigroup.com
Strict-Transport-Security: max-age=63072000; includeSubdomains; preload
security.txt present
Found security.txt at https://citigroup.com/.well-known/security.txt.
TLS certificate valid for 152 days
Certificate for citigroup.com expires on 2026-10-08.
Certificate issued by DigiCert EV RSA CA G2
The certificate for citigroup.com is issued by a third-party CA.
Signature algorithm: rsa-sha256
The certificate for citigroup.com uses an acceptable signature algorithm.
RSA key: 2048 bits
The certificate for citigroup.com uses an adequate RSA key of 2048 bits.
SCTs present in certificate
The certificate for citigroup.com contains Signed Certificate Timestamps.
No weak ciphers detected
No known weak cipher suites detected on citigroup.com.
TLD has good reputation
The .com TLD is not on known abuse watchlists.
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-b.mail.citi.com) uses with cipher including Forward Secrecy.
SMTP banner matches infrastructure identity
The SMTP banner (mx-b.mail.citi.com) aligns with the MX hostname (mx-b.mail.citi.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.
Could not connect to webmail.citigroup.com
HTTPS request to https://webmail.citigroup.com failed or timed out.
WHOIS lookup failed
Could not retrieve WHOIS data for citigroup.com.
Typosquat detected: itigroup.com (has MX!), ctigroup.com (has MX!), citgroup.com (has MX!), ictigroup.com (has MX!), citigropu.com (has MX!)
18 registered lookalike domain(s) that could be used for phishing against your brand. Showing top 5 of 18. 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
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DMARC Policy
DMARC policy: reject
DMARC Authentication Chain (DKIM)
DMARC uses DKIM to verify that emails have not been tampered with
DKIM Signature
DKIM signature missing
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DMARC Policy
DMARC policy: reject
⚠️ 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-a.mail.citi.com
PTR record proves mail server legitimacy
MX: mx-a.mail.citi.com
Mail server at 67.231.145.106
→
PTR Record
Reverse DNS: mx-a.mail.citi.com
Mail Server Identity: mx-b.mail.citi.com
PTR record proves mail server legitimacy
MX: mx-b.mail.citi.com
Mail server at 67.231.153.94
→
PTR Record
Reverse DNS: mx-b.mail.citi.com
Mail Server Reputation: mx-a.mail.citi.com
RBL check ensures server is not blacklisted
MX: mx-a.mail.citi.com
Mail server at 67.231.145.106
→
RBL Status
Not blacklisted
Mail Server Reputation: mx-b.mail.citi.com
RBL check ensures server is not blacklisted
MX: mx-b.mail.citi.com
Mail server at 67.231.153.94
→
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
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MTA-STS Policy
MTA-STS not configured
⚠️ MTA-STS policy is missing. Even with TLS support, you lack the enforcement layer that prevents attackers from stripping encryption (downgrade attacks).
Brand Identity Chain
BIMI displays your logo in email clients, but requires DMARC enforcement
DMARC Enforcement
DMARC policy: reject
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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
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TLS-RPT Reporting
TLS-RPT not configured
⚠️ TLS-RPT is not configured. Without TLS reporting, you have no visibility into TLS connection failures that may be impacting email delivery.
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/citigroup.com.svg" alt="Email Security Grade">
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