vulnerability scan
also: security scan, penetration scan, vuln scan
An automated or manual process that examines a system for known security weaknesses, misconfigurations, or outdated software that could be exploited by attackers.
A vulnerability scan systematically probes a Linux system or network to identify potential security flaws before attackers can exploit them. Tools perform checks against databases of known vulnerabilities, missing patches, weak passwords, open ports, and configuration errors.
Common vulnerability scanners include Nessus, OpenVAS, Qualys, and Rapid7 Nexpose. For example, a scan might detect that a web server is running an outdated version of Apache with a known remote code execution flaw, or that SSH is configured to allow root login.
Vulnerability scanning is a critical part of security hardening and compliance. Results are typically prioritized by severity (critical, high, medium, low) so administrators can patch the most dangerous issues first.
Note: scanning should only be performed on systems you own or have explicit permission to test, as it can trigger security alerts or temporarily impact system performance.