Attack surface

(also threat surface, vulnerability surface)

Attack surface definition

Attack surface refers to the cumulative vulnerabilities or points of entry that an attacker can exploit to launch a cyberattack against a system, network, or application. This includes software and hardware components, network interfaces, and services that are accessible to unauthorized users. Reducing the attack surface is a key aspect of improving a system's security posture, and it involves minimizing unnecessary services. Implementing strong access controls and applying security patches in a timely manner are recommended.

See also: buffer overflow attack, vulnerability, end-to-end encryption

Attack surface examples

  • Open ports: Unsecured network ports can give attackers an entry point into a system or network. Closing unnecessary ports helps reduce the attack surface.
  • Outdated software: Software that hasn't been updated or patched may contain security vulnerabilities, making it an attractive target for cybercriminals.
  • Weak or default passwords: Weak or default passwords are easy to guess or crack, providing a potential entry point for attackers.

Attack surface reduction tips

  • Keep software and systems updated and patched to eliminate known vulnerabilities.
  • Enforce strong password policies and use multi-factor authentication.
  • Regularly review user access and permissions, granting only the minimum necessary access.
  • Implement network segmentation to isolate critical systems and limit lateral movement.
  • Use a VPN, like NordVPN, to encrypt your internet connection and protect your online activities.