Query: stealth using Extra Window Memory Injection
Matching passage: T1055.011 Extra Window Memory Injection. Tactics: stealth, privilege escalation. Description: Adversaries may inject malicious code into process via Extra Window Memory (EWM) in order to evade process-based defenses as well as possibly elevate privileges. EWM injection is a method of executing arbitrary code in the address space of a separate live process. Before creating a window, graphical Windows-based processes must prescribe to or register a windows class, which stipulate appearance and behavior (via windows procedures, which are functions that handle input/output of data).(Citation: Microsoft Window Classes) Registration of new windows classes can include a request for up to 40 bytes of EWM to be appended to the allocated memory of each instance of that class. This EWM is intended to store data specific to that window and has specific application programming interface (API) functions to set and get its value. (Citation: Microsoft GetWindowLong function) (Citation: Microsoft SetWindowLong function) Although small, the EWM is large enough to store a 32-bit pointer and is often used to point to a windows procedure. Malware may possibly utilize this memory location in part of an attack chain that includes writing code to shared sections of the process’s memory, placing a pointer to the code in EWM, then invoking execution by returning execution control to the address in the process’s EWM. Execution granted through EWM injection may allow access to both the target process's memory and possibly elevated privileges. Writing payloads to shared sections also avoids the use of highly monitored API calls such as <code>WriteProcessMemory</code> and <code>CreateRemoteThread</code>.(Citation: Elastic Process Injection July 2017) More sophisticated malware samples may also potentially bypass protection mechanisms such as data execution prevention (DEP) by triggering a combination of windows procedures and other system functions that will rewrite the malicious payload inside an executable portion of the target process. (Citation: MalwareTech Power Loader Aug 2013) (Ci
Near-miss passage: T1055.015 ListPlanting. Tactics: stealth, privilege escalation. Description: Adversaries may abuse list-view controls to inject malicious code into hijacked processes in order to evade process-based defenses as well as possibly elevate privileges. ListPlanting is a method of executing arbitrary code in the address space of a separate live process.(Citation: Hexacorn Listplanting) Code executed via ListPlanting may also evade detection from security products since the execution is masked under a legitimate process. List-view controls are user interface windows used to display collections of items.(Citation: Microsoft List View Controls) Information about an application's list-view settings are stored within the process' memory in a <code>SysListView32</code> control. ListPlanting (a form of message-passing "shatter attack") may be performed by copying code into the virtual address space of a process that uses a list-view control then using that code as a custom callback for sorting the listed items.(Citation: Modexp Windows Process Injection) Adversaries must first copy code into the target process’ memory space, which can be performed various ways including by directly obtaining a handle to the <code>SysListView32</code> child of the victim process window (via Windows API calls such as <code>FindWindow</code> and/or <code>EnumWindows</code>) or other [Process Injection](https://attack.mitre.org/techniques/T1055) methods. Some variations of ListPlanting may allocate memory in the target process but then use window messages to copy the payload, to avoid the use of the highly monitored <code>WriteProcessMemory</code> function. For example, an adversary can use the <code>PostMessage</code> and/or <code>SendMessage</code> API functions to send <code>LVM_SETITEMPOSITION</code> and <code>LVM_GETITEMPOSITION</code> messages, effectively copying a payload 2 bytes at a time to the allocated memory.(Citation: ESET InvisiMole June 2020) Finally, the payload is triggered by sending the <code>LVM_SORTITEMS</code> message to the <code>SysListView32</code>