Incident Response Playbook for Phishing Attacks (Updated 2025)

This Phishing Incident Response Playbook provides a step-by-step guide to handle phishing attacks, from detection to recovery and continuous improvement. It includes enhanced procedures for monitoring, containment, communication, and regulatory compliance based on modern security practices.

1. Preparation

Objective: Implement security measures and establish contacts to ensure a rapid and effective response to phishing attacks.

Key Steps:

1. Define Contacts and Escalation Procedures:

   • Maintain an updated list of internal contacts, including SOC analysts, incident response teams, legal advisors, and communications teams.

   • Identify external contacts, such as CERTs, hosting providers, and domain registrars.

2. Configure Security Infrastructure:

   • Deploy and configure anti-phishing technologies, including:

     • DKIM, DMARC, and SPF to authenticate emails.

     • Web Application Firewalls (WAFs) to monitor incoming traffic.

     • Email filtering tools and spam traps to detect suspicious emails.

3. Prepare Awareness Campaigns:

   • Educate employees and customers on how to identify phishing attempts.

   • Regularly communicate that your organisation will never request credentials or sensitive information through email.

4. Monitoring Tools:

   • Implement continuous monitoring of:

     • Cybersquatting domains and phishing repositories (e.g., PhishTank).

     • Suspicious email patterns and website traffic.

     • Referrer URLs pointing to your legitimate website.

5. Create Emergency Response Assets:

   • Prepare a phishing alert page hosted on your infrastructure, ready for immediate deployment.

   • Pre-configure email templates to contact hosting providers and request phishing website takedowns.

2. Identification

Objective: Detect phishing attacks, determine their scope, and notify relevant parties.

Detection Techniques:

1. Monitoring Channels:

   • Monitor internal and external points of contact (e.g., email, web forms, phone reports).

   • Deploy automated systems to monitor phishing repositories (e.g., Google Safe Browsing, PhishTank) and alert when detections occur.

2. Analyse Suspicious Emails:

   • Check for:

     • Spoofed sender addresses.

     • Malicious links or attachments.

     • Unusual requests for sensitive information.

3. Log Analysis:

   • Review web server and proxy logs to detect redirection patterns from phishing websites to your legitimate site.

4. Evidence Collection:

   • Save a timestamped copy of the phishing website and email, including source code and screenshots.

   • Identify where the data captured by the phishing website is sent (e.g., email accounts, external servers).

5. Notify Decision-Makers:

   • Inform authorised personnel within your organisation to approve further actions.

3. Containment

Objective: Limit the impact of the phishing attack on your organisation and customers.

Steps:

1. Block Malicious URLs:

   • Report the phishing URL to browser vendors (e.g., Chrome, Firefox, Safari) to block access for users.

   • Submit reports to anti-phishing initiatives and toolbars (e.g., Netcraft).

2. Notify Users:

   • Deploy the phishing alert page on your website, warning customers about the attack.

   • If attacks are frequent, maintain a static phishing awareness page instead of frequent warnings.

3. Spread Awareness:

   • Share the phishing email and URL with spam-reporting platforms to prevent further spread.

4. Remediation

Objective: Take immediate action to stop the phishing campaign.

Steps:

1. Contact Hosting Providers:

   • If the phishing website is hosted on a compromised domain, notify the domain owner to secure and remove malicious content.

   • Contact the hosting provider to initiate a takedown request.

2. Disable Malicious Accounts:

   • Contact email service providers hosting phishing-related email accounts to shut them down.

   • Request takedown of redirecting services if the phishing email contains intermediate redirection links.

3. Escalate Unresponsive Cases:

   • If takedown efforts stall, escalate the request through CERTs or law enforcement agencies in the relevant jurisdiction.

4. Document All Actions:

   • Record the timeline and correspondence with hosting providers, CERTs, and other stakeholders.

5. Recovery

Objective: Restore systems and operations to normal while ensuring that the phishing threat is fully mitigated.

Steps:

1. Monitor and Verify:

   • Ensure that the phishing website and email addresses are no longer active.

   • Continue monitoring for reactivation of malicious domains or redirections.

2. Remove Temporary Alerts:

   • Once the phishing campaign is confirmed to be over, remove the alert page from your website.

3. Assess Impact:

   • Identify any compromised accounts or data and implement further recovery actions (e.g., forced password resets).

6. Lessons Learned

Objective: Analyse the incident, document findings, and improve response capabilities.

Steps:

1. Incident Report:

   • Include the following details:

     • Initial detection and cause.

     • Key actions taken and their timelines.

     • Lessons learned, including strengths and weaknesses in the response process.

2. Evaluate and Improve:

   • Identify areas where detection, containment, or communication could be improved.

   • Update response playbooks, contact lists, and security policies as needed.

3. Training and Awareness:

   • Reinforce phishing awareness training for both employees and customers.

   • Conduct phishing simulations to test response readiness.

4. Collaboration:

   • Strengthen relationships with hosting providers, CERTs, and law enforcement to streamline future incident handling.

Conclusion

This Phishing Incident Response Playbook equips organisations with a comprehensive approach to handle phishing attacks effectively. Regular training, updated monitoring tools, and proactive communication strategies are key to reducing the impact of phishing incidents.

For additional resources, including phishing takedown templates, monitoring tool recommendations, and awareness materials, please contact the cybersecurity operations team.