Query: Encoded PowerShell / command-line abuse matching Plist File Modification
Matching passage: T1647 Plist File Modification. Tactics: defense impairment. Description: Adversaries may modify property list files (plist files) to enable other malicious activity, while also potentially evading and bypassing system defenses. macOS applications use plist files, such as the <code>info.plist</code> file, to store properties and configuration settings that inform the operating system how to handle the application at runtime. Plist files are structured metadata in key-value pairs formatted in XML based on Apple's Core Foundation DTD. Plist files can be saved in text or binary format.(Citation: fileinfo plist file description) Adversaries can modify key-value pairs in plist files to influence system behaviors, such as hiding the execution of an application (i.e. [Hidden Window](https://attack.mitre.org/techniques/T1564/003)) or running additional commands for persistence (ex: [Launch Agent](https://attack.mitre.org/techniques/T1543/001)/[Launch Daemon](https://attack.mitre.org/techniques/T1543/004) or [Re-opened Applications](https://attack.mitre.org/techniques/T1547/007)). For example, adversaries can add a malicious application path to the `~/Library/Preferences/com.apple.dock.plist` file, which controls apps that appear in the Dock. Adversaries can also modify the <code>LSUIElement</code> key in an application’s <code>info.plist</code> file to run the app in the background. Adversaries can also insert key-value pairs to insert environment variables, such as <code>LSEnvironment</code>, to enable persistence via [Dynamic Linker Hijacking](https://attack.mitre.org/techniques/T1574/006).(Citation: wardle chp2 persistence)(Citation: eset_osx_flashback)
Near-miss passage: T1553.003 SIP and Trust Provider Hijacking. Tactics: defense impairment. Description: Adversaries may tamper with SIP and trust provider components to mislead the operating system and application control tools when conducting signature validation checks. In user mode, Windows Authenticode (Citation: Microsoft Authenticode) digital signatures are used to verify a file's origin and integrity, variables that may be used to establish trust in signed code (ex: a driver with a valid Microsoft signature may be handled as safe). The signature validation process is handled via the WinVerifyTrust application programming interface (API) function, (Citation: Microsoft WinVerifyTrust) which accepts an inquiry and coordinates with the appropriate trust provider, which is responsible for validating parameters of a signature. (Citation: SpectorOps Subverting Trust Sept 2017) Because of the varying executable file types and corresponding signature formats, Microsoft created software components called Subject Interface Packages (SIPs) (Citation: EduardosBlog SIPs July 2008) to provide a layer of abstraction between API functions and files. SIPs are responsible for enabling API functions to create, retrieve, calculate, and verify signatures. Unique SIPs exist for most file formats (Executable, PowerShell, Installer, etc., with catalog signing providing a catch-all (Citation: Microsoft Catalog Files and Signatures April 2017)) and are identified by globally unique identifiers (GUIDs). (Citation: SpectorOps Subverting Trust Sept 2017) Similar to [Code Signing](https://attack.mitre.org/techniques/T1553/002), adversaries may abuse this architecture to subvert trust controls and bypass security policies that allow only legitimately signed code to execute on a system. Adversaries may hijack SIP and trust provider components to mislead operating system and application control tools to classify malicious (or any) code as signed by: (Citation: SpectorOps Subverting Trust Sept 2017) * Modifying the <code>Dll</code> and <code>FuncName</code> Registry values in <code>HKLM\SOFTWARE