Fixing Missing DMARC Record
Vulnerability assessment details, CWE reference metrics, and complete code-level patches.
Threat Profile
Vulnerability Analysis
DMARC verifies that emails sent from a domain match the records specified in SPF and DKIM profiles. If missing, servers cannot verify sender identities.
How it is Detected
Identified by querying the domain's TXT DNS records for prefix '_dmarc'.
Remediation Guidelines
Publish a valid DMARC TXT record in your DNS settings.
Remediation Script (DNS TXT Record)
# SECURE REMEDIATION: Sample strict DMARC record
_dmarc.example.com. IN TXT "v=DMARC1; p=reject; pct=100; rua=mailto:dmarc-reports@example.com"Frequently Asked Questions
What is DMARC?
DMARC is a DNS record that coordinates how receivers process emails that fail SPF or DKIM verification.
What does 'p=reject' mean?
It tells receiving servers to reject unauthorized emails completely, preventing email spoofing.
How do I monitor DMARC failures?
Specify report email addresses using the 'rua' and 'ruf' flags in the DMARC TXT record.
Related Vulnerability Profiles
SQL Injection (SQLi)
Attackers execute arbitrary SQL commands, bypassing authentication and manipulating database schemas.
Stored Cross-Site Scripting (Stored XSS)
Malicious scripts are stored on the server (e.g. database) and executed when users request the compromised resource.
Reflected Cross-Site Scripting (Reflected XSS)
Malicious scripts are reflected off the web server (e.g. search queries) and executed immediately in the user's browser.
DOM-based Cross-Site Scripting (DOM XSS)
Vulnerability where the client-side JavaScript processes inputs in an unsafe way (e.g. using eval or innerHTML).