Third-Party Cyber Attacks: How to Shield Your Business from Sneaky Hackers
Your business isn’t an island. You rely on vendors, suppliers, and software tools—your “digital neighbors”—to keep things running. But here’s the scary truth: third-party cyber attacks are skyrocketing. In 2024, 60% of data breaches started with a weak link in a partner’s system. Hackers love targeting third parties because they’re often the easiest way into your network. Think of it like burglars sneaking through an unlocked back door. In this guide, we’ll show you how to spot these risks, lock down your partnerships, and avoid becoming the next headline. Let’s get started!
Understanding Third-Party Cyber Attacks
What Are Third-Party Cyber Attacks?
A third-party cyber attack happens when hackers breach your business through a partner, vendor, or service you trust. For example:
A hacker steals your accounting firm’s data by breaking into your payroll software provider.
A phishing email sent to your delivery contractor tricks them into sharing your network access.
Common Attack Vectors
Vendors: Suppliers with weak passwords or outdated software.
Software Tools: Apps or platforms with security gaps (e.g., a hacked CRM).
Contractors: Remote workers using unsecured Wi-Fi.
Real-World Example: The SolarWinds Hack
In 2020, hackers inserted malware into SolarWinds’ software updates. Thousands of companies (including U.S. government agencies) were infected just by updating their systems
Pro Tip: Treat third-party risks like secondhand smoke—your partners’ bad habits can hurt you.
Why Third-Party Risks Are Escalating in 2025
1. Cloud Services & SaaS Overload
Businesses use 130+ cloud apps on average. Each app is a potential entry point for hackers.
2. AI-Powered Attacks
Hackers now use AI to:
Create fake invoices that look real.
Impersonate CEOs using deepfake voice calls.
3. Remote Work Weaknesses
Home Wi-Fi networks and personal devices are easy targets for stealing login info.
Action Step: Audit all third-party tools your team uses—start with the most sensitive ones (e.g., payroll, CRM).
Key Vulnerabilities in Third-Party Relationships
1. Unpatched Software
Problem: Vendors are using outdated software with known security holes.
Example: A retailer’s HVAC vendor got hacked because they didn’t update their system, leading to a massive data breach
2. No Vendor Security Checks
Many businesses skip background checks on partners.
Solution: Ask vendors, “How do you protect our data?”
3. Poor Access Control
Contractors with full network access (instead of limited permissions).
Fix: Use “least privilege” rules—only grant access to what’s needed.
How to Identify and Assess Third-Party Risk
1. Vendor Risk Assessments
Ask partners these questions:
Do you encrypt data?
How often do you update software?
Do you have a response plan for breaches?
2. Use Cybersecurity Ratings
Tools like SecurityScorecard or BitSight rate vendors’ security (like a credit score).
3. Map Data Flows
Track where your data goes (e.g., from your CRM to a marketing agency).
Use flowcharts to spot risky connections.
Pro Tip : Start with your top 5 vendors—these usually pose the biggest risk.
Building a Resilient Third-Party Security Strategy
1. Zero Trust Architecture
What It Is: Assume no one is trustworthy until proven otherwise.
How : Require multi-factor authentication (MFA) for all access.
2. Enforce MFA Everywhere
Require codes (via SMS or apps) for logging in.
Bonus: Use hardware keys for ultra-sensitive systems.
3. Incident Response Planning
Create a step-by-step plan for breaches (e.g., who to call, how to contain damage).
Practice with drills involving your vendors.
Compliance and Regulatory Considerations
Key Regulations
GDPR: Fines up to 4% of revenue for mishandling EU data.
CCPA: Protects California residents’ data.
NIST Framework: Guidelines for managing third-party risks.
How to Stay Compliant
Document all vendor contracts and security agreements.
Schedule annual audits to prove you’re following rules.
Example: A hospital was fined $2M for not checking a medical device vendor’s security
Tools and Technologies to Strengthen Vendor Security
1. Risk Management Platforms
OneTrust: Tracks vendor compliance.
Prevalent: Monitors risks in real time.
2. Continuous Monitoring
Use tools like CrowdStrike or Darktrace to detect suspicious activity.
3. Secure Onboarding/Offboarding
When hiring a vendor:
Sign data protection agreements.
Set up limited access.
When ending a partnership:
Revoke login permissions.
Delete shared data.
Case Studies: Lessons from Major Breaches
Case Study #1: MOVEit Transfer Hack (2023)
What Happened: Hackers exploited a file-transfer app used by thousands of companies.
Damage: Over 60 million people had their data stolen.
Lesson: Monitor third-party software for updates and vulnerabilities.
Case Study #2: Target Breach (2013)
What Happened: Attackers stole Target’s customer data via an HVAC vendor.
Cost: $18.5 million in fines.
Lesson: Vet all vendors, even those with “low-risk” access.
Conclusion
Third-party cyber attacks aren’t going away—in fact, they’ll keep getting worse. But you can fight back by:
Assessing vendor risks regularly.
Using tools like MFA and Zero Trust.
Staying compliant with regulations.
Your Action Plan for Next Week :
Audit the security of your top 5 vendors.
Enable MFA for all third-party logins.
Download our free Third-Party Risk Checklist (link below).
Don’t let someone else’s mistake become your disaster. Act now—your business’s future depends on it.