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intrusion
Intrusion
Definition
In cybersecurity, an **intrusion** is any unauthorized entry into a computer system, network, or application. It’s the digital equivalent of someone breaking into a building — except instead of forcing a door, the attacker exploits vulnerabilities, steals credentials, or tricks users into letting them in. An intrusion doesn’t have to mean data was stolen or systems were damaged — it simply means the attacker gained access without permission. From there, they might: * Steal data * Deploy malware or ransomware * Move laterally through the network * Install backdoors for future access Intrusions can happen through: * **Technical exploitation** – Using software vulnerabilities, weak passwords, or misconfigurations. * **Social engineering** – Phishing, pretexting, or other human-focused tactics. * **Physical access** – Plugging malicious devices into systems on-site. In investigations, detecting an intrusion often involves: * Reviewing **logs** for suspicious login attempts or anomalies * Monitoring for **new processes** or unusual network connections * Spotting **changes in configurations** or the presence of unauthorized tools * Correlating multiple small clues (failed logins, suspicious file creation, odd PowerShell commands) into a bigger picture
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Initial Access
Impact
Sha256
Investigation
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