T1181: Extra Window Memory Injection
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). [1] Registration of new windows classes can include a request for up to 40 bytes of extra window memory (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. [2] [3]
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 take place in the address space of a separate live process. Similar to Process Injection, this 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 WriteProcessMemory and CreateRemoteThread. [4] 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. [5] [6]
This ATT&CK object is revoked or deprecated in the current MITRE ATT&CK release.
It remains available for historical context and inbound links. Use current ATT&CK relationships and replacement guidance before basing detection or reporting work on this page.
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Extra Window Memory Injection
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). [1] Registration of new windows classes can include a request for up to 40 bytes of extra window memory (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. [2] [3]
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 take place in the address space of a separate live process. Similar to Process Injection, this 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 WriteProcessMemory and CreateRemoteThread. [4] 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. [5] [6]
How security teams should use this page
Treat this object as behavior context, not an attribution claim. Validate the related groups, software, data sources, and mitigations against official ATT&CK relationships and your own telemetry before making control-coverage decisions.
Related techniques
This mirrors the MITRE pattern of making group, software, campaign, and technique relationships scannable. Relationship notes come from mirrored ATT&CK relationship text when available.
| Domain | ID | Name | Relationship / procedure |
|---|---|---|---|
| Enterprise | T1055.011 | Extra Window Memory InjectionSub-technique | This object revoked by Extra Window Memory Injection. |
All related ATT&CK context
Object version and sync metadata
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Imported snapshots across ATT&CK releases(1)
| Release | Bundle imported | Object version | Modified | Status | Raw hash |
|---|---|---|---|---|---|
| 19.1 | 1.1 | Current bundleRevoked | 28c669fb9a9d… |
Mirrored ATT&CK source object
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External references and citations
MITRE external references are preserved separately from Glexia analysis so citations remain traceable to their original source records.
- [1]Microsoft Window Classes
Microsoft. (n.d.). About Window Classes. Retrieved December 16, 2017.
Open source URL - [2]Microsoft GetWindowLong function
Microsoft. (n.d.). GetWindowLong function. Retrieved December 16, 2017.
Open source URL - [3]Microsoft SetWindowLong function
Microsoft. (n.d.). SetWindowLong function. Retrieved December 16, 2017.
Open source URL - [4]Elastic Process Injection July 2017
Hosseini, A. (2017, July 18). Ten Process Injection Techniques: A Technical Survey Of Common And Trending Process Injection Techniques. Retrieved December 7, 2017.
Open source URL - [5]MalwareTech Power Loader Aug 2013
MalwareTech. (2013, August 13). PowerLoader Injection – Something truly amazing. Retrieved December 16, 2017.
Open source URL - [6]WeLiveSecurity Gapz and Redyms Mar 2013
Matrosov, A. (2013, March 19). Gapz and Redyms droppers based on Power Loader code. Retrieved December 16, 2017.
Open source URL - [7]Elastic Process Injection July 2017
Hosseini, A. (2017, July 18). Ten Process Injection Techniques: A Technical Survey Of Common And Trending Process Injection Techniques. Retrieved December 7, 2017.
Open source URL - [8]Elastic Process Injection July 2017
Hosseini, A. (2017, July 18). Ten Process Injection Techniques: A Technical Survey Of Common And Trending Process Injection Techniques. Retrieved December 7, 2017.
Open source URL - [9]MalwareTech Power Loader Aug 2013
MalwareTech. (2013, August 13). PowerLoader Injection – Something truly amazing. Retrieved December 16, 2017.
Open source URL - [10]MalwareTech Power Loader Aug 2013
MalwareTech. (2013, August 13). PowerLoader Injection – Something truly amazing. Retrieved December 16, 2017.
Open source URL - [11]Microsoft GetWindowLong function
Microsoft. (n.d.). GetWindowLong function. Retrieved December 16, 2017.
Open source URL - [12]Microsoft GetWindowLong function
Microsoft. (n.d.). GetWindowLong function. Retrieved December 16, 2017.
Open source URL - [13]Microsoft SendNotifyMessage function
Microsoft. (n.d.). SendNotifyMessage function. Retrieved December 16, 2017.
Open source URL - [14]Microsoft SendNotifyMessage function
Microsoft. (n.d.). SendNotifyMessage function. Retrieved December 16, 2017.
Open source URL - [15]Microsoft SendNotifyMessage function
Microsoft. (n.d.). SendNotifyMessage function. Retrieved December 16, 2017.
Open source URL - [16]Microsoft SetWindowLong function
Microsoft. (n.d.). SetWindowLong function. Retrieved December 16, 2017.
Open source URL - [17]Microsoft SetWindowLong function
Microsoft. (n.d.). SetWindowLong function. Retrieved December 16, 2017.
Open source URL - [18]Microsoft Window Classes
Microsoft. (n.d.). About Window Classes. Retrieved December 16, 2017.
Open source URL - [19]Microsoft Window Classes
Microsoft. (n.d.). About Window Classes. Retrieved December 16, 2017.
Open source URL - [20]WeLiveSecurity Gapz and Redyms Mar 2013
Matrosov, A. (2013, March 19). Gapz and Redyms droppers based on Power Loader code. Retrieved December 16, 2017.
Open source URL - [21]WeLiveSecurity Gapz and Redyms Mar 2013
Matrosov, A. (2013, March 19). Gapz and Redyms droppers based on Power Loader code. Retrieved December 16, 2017.
Open source URL - [22]mitre-attackT1181Open source URL
- [23]mitre-attackT1181Open source URL
- [24]mitre-attackT1181Open source URL
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