Email Security 2026: DMARC Enforcement, BEC & Deepfake Impersonation

Email remains the backbone of business communication—and the #1 entry point for attacks. In 2026, major providers will tighten requirements for authentication and reporting, while attackers in Business Email Compromise (BEC) increasingly rely on deepfake voices and convincing identity spoofs. This guide explains what’s changing and which controls deliver measurable impact now: from DMARC to MFA enforcement and payment controls.

 The 4 key points

• DMARC set to “reject” (with clean reporting) is becoming the de facto standard—incl. proper alignment for SPF/DKIM.
• Enforce MFA—preferably phishing-resistant—for admin and VIP accounts.
• BEC & deepfakes blend social engineering with voices/avatars: out-of-band callbacks and payment policies are mandatory.
• Time-of-click link inspection, attachment sandboxing & DNS/NRD blocking close gaps beyond the inbox.

Threat landscape 2026: BEC & deepfake impersonation

BEC campaigns use compromised or spoofed identities, often reinforced by deepfake calls (“The CFO needs a payment right now”). Technically clean emails can still deceive—so you need process guardrails outside of email.

Controls that actually work

1) Authentication & email protection

• SPF, DKIM, DMARC (p=reject) with active DMARC reporting (rua/ruf) and proper alignment per sending source.
• Time-of-click inspection for links, attachment sandboxing (including protected archives), and DNS/web filtering incl. NRD blocking (newly registered domains).
• User-friendly warning banners (“External sender,” “look-alike domain”) and a phish-report button in the client.

2) Identity & access (MFA enforcement)

• Enforce phishing-resistant MFA (FIDO2/WebAuthn), at least for admins, finance roles, and executives.
• Conditional access: geo-blocking, risk sign-in policies, device compliance; hinder token theft via short-lived tokens and re-auth gates.
• Just-in-time admin rights + privileged access management with approval flows.

3) Payment controls against BEC

• Four-eyes principle and out-of-band callbacks (return call via known number) for account/IBAN changes and payments > threshold.
• Approval workflows in ERP/accounting with a time delay (e.g., 15 minutes) and mandatory justification.
• Whitelists/payment lock for vendor master data, change logs, and a hold period before payout.
• Card controls: limits, MCC blocks, geo restrictions; on suspicion: immediate block + callback.

4) Monitoring & response

• XDR/EDR for compromised devices & tokens; central SIEM use cases (e.g., “unusual forwarding,” “OAuth app consent,” “inbox rules”).
• IR playbooks for BEC: end sessions, revoke auth tokens, delete mailbox rules, update blocklists, inform bank/partners.

Need help?

Learn more: Email Security

Note: Requirements and provider policies evolve continuously. Always check your email provider’s current guidance and your compliance frameworks.