One term that consistently emerges as a foundation of digital protection is Defensive Security. While Offensive Security focuses on attacking systems to uncover vulnerabilities (ethical hacking), Defensive Security is about protecting systems, networks, and data from unauthorized access, damage, or disruption. In other words, it’s your linebacker reading the offense.
What is Defensive Security?
Defensive Security encompasses the protocols used to prevent and respond to cyber threats. Its goal is to build a robust infrastructure that withstands cyber-attacks, whether they come from hackers or highly sophisticated threat actors.
Key elements of Defensive Security include:
· Firewalls and intrusion detection systems (IDS)
· Endpoint Protection and antivirus software
· Network segmentation
· Security information and event management (SIEM)
· Patch management
· User education and awareness
Best Practices for Good Defensive Security
A strong defense doesn’t come from a single tool or policy, it requires a layered, strategic approach. Here are some widely recognized best practices:
Implement a Defense-in-Depth Strategy
This involves layering multiple security controls throughout your IT environment. If one layer fails, others are in place to prevent a breach.
Patch and Update Regularly
Unpatched systems are one of the most common attack vectors. Regularly updating software, firmware, and operating systems closes known vulnerabilities before attackers can exploit them.
Use Less Privilege Access
Employees and systems should only have the access they need. This limits the blast radius of a compromised account.
Conduct Regular Security Audits and Risk Assessments
Assess your system’s vulnerabilities proactively. Identify and fix weaknesses before attackers do. Regular audits help uncover shadow IT, misconfigurations, and outdated practices.
Employee Education
Human error remains a top cause of security incidents.
Prepare and Practice Incident Response
Have a clear plan in place in case of a breach. Practice it regularly through tabletop exercises or simulations to improve response time and effectiveness. Don’t have a plan? Contact us now to begin developing your Incident Response Plan.
Defensive Security is not a one-time effort, it’s an ongoing discipline that evolves alongside the threat landscape. Organizations that prioritize layered defenses, employee training, and proactive monitoring are better positioned to prevent breaches and minimize damage when incidents occur.
References
MITRE ATT&CK®, https://attack.mitre.org/. Accessed 7 April 2025.
“least privilege - Glossary | CSRC.” NIST Computer Security Resource Center, https://csrc.nist.gov/glossary/term/least_privilege. Accessed 3 April 2025.
“Security and Privacy Controls for Information Systems and Organizations.” NIST Technical Series Publications, 5 September 2020, https://nvlpubs.nist.gov/nistpubs/SpecialPublications/NIST.SP.800-53r5.pdf. Accessed 7 April 2025.
“2025 Data Breach Investigations Report.” Verizon, https://www.verizon.com/business/resources/reports/dbir/. Accessed 4 April 2025.
About Solis
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