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type: link
tags: [email, security, protocol]
created: 2025-12-26T16:37:55.53+00:00
updated: 2026-01-02T01:39:32.364Z
---# Mail Transfer Agent Strict Transport Security (mta-sts)

**URL:** [https://search.brave.com/search?q=mta-sts](https://search.brave.com/search?q=mta-sts)

mta-sts Mail Transfer Agent Strict Transport Security (MTA-STS) is an email security standard for secure delivery of email to your domain. With MTA-STS you let senders know that your email server accepts secure email delivery using SMTP over TLS (STARTTLS), and that email should not be delivered over an insecure SMTP connection.MTA-STS mitigates Man-In-The-Middle DNS and SMTP downgrade attacks that would allow an attacker to read or manipulate email in transit.


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**Keywords:** email, security, protocol
