Section 21.204 Email Secuirty Flashcards
Objective 4.1 Given a scenario, you must be able to apply common security techniques to computing resources. Objective 4.5 Given a scenario, you must be able to modify enterprise capabilities to enhance security.
Email Security
Encompasses techniques and protocols to protect email content, accounts, and infrastructure from unauthorised access, loss, or compromise
Key email security techniques
DKIM (DomainKeys Identified Mail)
Allows the receiver to verify the source and integrity of an email by adding a digital signature to the email headers
● The recipient server validates the DKIM signature using the sender’s public cryptographic key in the domain’s DNS records
● Benefits:
○ Email authentication
○ Protection against email spoofing
○ Improved email deliverability
○ Enhanced reputation score
Key email security techniques
SPF (Sender Policy Framework)
Prevents sender address forgery by verifying the sender’s IP against
authorised IPs listed in the sender’s domain DNS records
● A receiving server checks if the sender’s IP is authorized in the SPF record before accepting the email
● Benefits:
○ Preventing email spoofing
○ Improving email deliverability
○ Enhancing the domain’s reputation
Key email security techniques
DMARC (Domain-based Message Authentication, Reporting and Conformance)
DMARC detects and prevents email spoofing by setting policies for email
sending and handling failures
● DMARC can work with DKIM, SPF, or both
● Implementation helps protect against:
○ Business email compromise attacks
○ Phishing
○ Scams
○ Cyber threats
Key email security techniques
Email Gateway Protocol Configuration
Email gateways serve as entry and exit points for emails, facilitating secure and efficient email transmission
● They use SMTP (Simple Mail Transfer Protocol) to send and receive emails
● Email gateways handle email routing, email security, policy enforcement, and email encryption
Email Gateway Deployment Options
On-Premises Email Gateway
A physical server located within an organisation’s premises, offering full control but requiring maintenance and updates
Email Gateway Deployment Options
Cloud-Based Email Gateway
Hosted by third-party cloud service providers, providing scalability but limited control over configurations
Email Gateway Deployment Options
Hybrid Email Gateway
Combines on-premises and cloud-based gateways for a balance between control and convenience
Spam Filtering
Spam filtering detects and prevents unwanted and unsolicited emails from
reaching users’ inboxes
■ Techniques:
● Content analysis
● Bayesian filtering
● DNS-based sinkhole list
● Email filtering rules
Emails with spam-like keywords are flagged and often moved to the spam folder
