Is Your Email Leaking Data? How to Check Email Reputation
Learn why email reputation matters for security and deliverability, and how to check if an email address is compromised or malicious.
Jean-Vincent QUILICHINI
The Trust Score of the Internet
Every email address has a reputation. Just like a credit score, this reputation determines whether your emails land in the inbox or the spam folder—and whether receiving servers trust you. But email reputation isn't just for marketers; it's a critical security metric.
Why Email Reputation Matters
- For Businesses: A poor domain reputation means your legitimate emails get blocked.
- For Security: Attackers often use low-reputation or newly created emails for phishing. If you receive an email from an address with a "bad" score, it's a red flag.
Factors Influencing Reputation
- Blacklists: Is the sending IP or domain on a known spam list?
- Volume Spikes: Sending 10,000 emails suddenly looks suspicious.
- Authentication: Lack of SPF, DKIM, or DMARC records makes spoofing easy.
How to Check Email Threats
Before you click a link or reply to a suspicious message:
- Verify the Source: Use our tools to check the domain of the sender.
- Look for Spoofing: Attackers often use "cousin domains" (e.g.,
support@paypa1.com). - Scan for Breaches: Has this email been involved in known data leaks?
Protecting Your Own Reputation
- Authenticate: Set up SPF, DKIM, and DMARC.
- Clean Your Lists: Remove inactive users to keep engagement high.
- Monitor: Regularly check your domain's health to ensure no one is spoofing your brand.
Email is the #1 entry point for cyberattacks. Treating email reputation seriously is your first line of defense.
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