Malicious payload delivery: In this scenario, attackers capitalize on DLL sideloading to deliver a malicious payload onto a victim's system. Consider an unsuspecting user downloading a seemingly harmless application from an untrusted source. The attacker strategically embeds a malicious DLL with the same name as a required DLL in the application's directory. When the user launches the application, Windows loads the malicious DLL instead of the legitimate one, facilitating the execution of unauthorized code. This breach compromises system integrity, potentially leading to data theft, unauthorized access, or total system control.
System escalation and privilege elevation: DLL sideloading can also enable attackers to escalate privileges and gain control over a victim's system. In an organizational context, a malicious actor may exploit a vulnerable application used by employees. By sideloading a malicious DLL into the application's directory, the attacker tricks the system into loading the malicious code instead of the intended DLL. This can lead to elevated system privileges, allowing attackers to bypass security controls, access sensitive data, and potentially compromise the entire network.
Espionage and data exfiltration: DLL sideloading can serve as a vehicle for cyberespionage, primarily when attackers target specific organizations or industries. Imagine an attacker infiltrating an organization by compromising a legitimate application for sharing confidential files. By sideloading a malicious DLL into the application's directory, the attacker can gain unauthorized access to sensitive documents, exfiltrate valuable information, and potentially compromise intellectual property, trade secrets, or customer data.
Evasion of security measures: Attackers often employ DLL sideloading to bypass security measures designed to detect and prevent unauthorized code execution. For instance, consider a scenario where an organization uses security software that monitors the integrity of known DLLs. An attacker sideloads a malicious DLL into a directory where the security software searches for legitimate DLLs. The attacker successfully evades detection by exploiting the security software's trust in the directory, allowing the malicious code to execute undetected.
Masking ransomware intrusion: In the context of ransomware attacks, attackers can use DLL sideloading to facilitate the initial intrusion. Attackers can bypass security measures and execute the ransomware code by embedding a ransomware payload within a malicious DLL and sideloading it into a legitimate application's directory. This initial intrusion opens the door for encrypting files, demanding ransom payments, and causing widespread disruption within the victim's organization.