Windows Smart App Control (previously known as Device Guard) is a feature in Windows that provides enhanced threat protection against various types of malicious software attacks. It's part of a larger set of security measures in Windows, including Windows Defender and other security features.
Here's what Windows Smart App Control specifically helps protect against:
- Unsigned Code: One of the primary functions of Smart App Control is to ensure that only signed applications and scripts run on the system. This can prevent the execution of malicious or unwanted software which hasn't been signed by a trusted publisher.
- Tampered Code: Even if a code or software is signed, it's possible for malicious actors to tamper with it post-signing. Smart App Control can block software that's been tampered with after it was signed.
- Credential Guard: It's an adjunct feature that uses virtualization to isolate secrets (like NTLM password hashes and Kerberos ticket-granting tickets) so that only privileged system software can access them, effectively mitigating pass-the-hash and related attacks.
Regarding DLL Hijacking:
DLL hijacking (or DLL side-loading) is a type of attack where malicious DLL files are used to hijack the loading process of legitimate DLLs expected by applications. This can allow attackers to execute malicious code in the context of the vulnerable application.
Windows Smart App Control can mitigate certain types of DLL hijacking attacks because it will enforce code integrity checks. If a malicious DLL hasn't been signed by a trusted signer, Smart App Control can prevent its execution.
However, it's important to understand that no single security measure is a silver bullet. While Smart App Control can prevent a significant number of threats, including many DLL hijacking attempts, there might be sophisticated attacks or configurations that bypass it. For comprehensive protection, a multi-layered security approach is always recommended. This includes keeping software updated, using strong and unique passwords, maintaining a reliable and updated anti-malware solution, and regularly educating users about security best practices.