IMAP over SSL/TLS: 933

Security Weaknesses:

• Vulnerable to misconfigured or outdated SSL/TLS versions.

• Susceptible to brute-force attacks if strong authentication is not enforced.

• Lack of end-to-end encryption could expose emails if intercepted at other points.

Security Defense and Mitigation Measures:

• Enforce TLS 1.2 or higher for secure communication.

• Implement rate limiting and account lockout policies for failed login attempts.

• Require multi-factor authentication (MFA) for email accounts.

• Regularly audit SSL/TLS certificates and server configurations.

Indicators of Compromise or Attack:

• Repeated login failures from unknown IP addresses.

• Expired or self-signed SSL/TLS certificates.

• Unusual activity in IMAP server logs, such as excessive data downloads.