Learn from Let's Encrypt

When 3 Million Certificates Had To Be Revoked
The Let's Encrypt CAA Bug

In 2020, Let's Encrypt faced a critical bug in their CAA (Certificate Authority Authorization) implementation, forcing them to revoke millions of certificates. Incident Drill helps your team prepare for similar high-stakes security incidents through realistic simulations and collaborative learning.

Let's Encrypt | 2020 | Security (CA incident)

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The High Cost of Security Vulnerabilities

Security vulnerabilities can lead to massive certificate revocations, damage reputation, and disrupt services. Lack of proper testing and validation of critical components like CAA checks can have far-reaching consequences, impacting millions of users and costing significant resources to remediate.

PREPARE YOUR TEAM

Simulate, Learn, and Prevent with Incident Drill

Incident Drill provides realistic incident simulations that allow your team to practice responding to security events like the Let's Encrypt CAA bug. Through collaborative drills and post-incident analysis, your team will develop the skills and processes needed to identify, contain, and resolve security vulnerabilities before they escalate.

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Realistic Simulations

Experience the pressure of a real security incident in a safe, controlled environment.

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Collaborative Drills

Work together as a team to investigate, diagnose, and resolve the incident.

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Root Cause Analysis

Dive deep into the underlying causes of the incident and identify areas for improvement.

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Performance Tracking

Measure your team's performance and identify areas where training is needed.

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Knowledge Base

Access a library of resources and best practices for incident response.

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Real-time Communication

Communicate and coordinate your response using built-in communication tools.

WHY TEAMS PRACTICE THIS

Mastering Certificate Security Incidents

✓ Improve incident response time
✓ Enhance team communication and collaboration
✓ Identify and address weaknesses in your security infrastructure
✓ Reduce the risk of future security breaches
✓ Increase confidence in your team's ability to handle critical incidents
✓ Ensure compliance with security regulations

CAA Validation Flow

Request

Certificate request initiated

CAA Check

CAA records queried for domain Expected: Allow Actual: Cache Bug

Certificate Issued

Certificate incorrectly issued due to cached CAA records

Revocation

Mass certificate revocation initiated

How It Works

Step 1: Incident Briefing

Understand the scope and impact of the Let's Encrypt CAA bug.

Step 2: Investigation & Diagnosis

Analyze the root cause of the bug and its impact on certificate issuance.

Step 3: Containment & Mitigation

Develop a plan to contain the incident and mitigate its impact.

Step 4: Post-Incident Review

Analyze the team's response and identify areas for improvement.

EXPLORE MORE

Related Incidents

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When 3 Million Certificates Had To Be Revoked The Let's Encrypt CAA Bug