Sub-technique of T1055 Process Injection.View on attack.mitre.org
Adversaries may inject malicious code into processes via the asynchronous procedure call (APC) queue in order to evade process-based defenses as well as possibly elevate privileges. APC injection is a method of executing arbitrary code in the address space of a separate live process.
APC injection is commonly performed by attaching malicious code to the APC Queue of a process's thread. Queued APC functions are executed when the thread enters an alterable state. A handle to an existing victim process is first created with native Windows API calls such as OpenThread. At this point QueueUserAPC can be used to invoke a function (such as LoadLibrayA pointing to a malicious DLL).
A variation of APC injection, dubbed "Early Bird injection", involves creating a suspended process in which malicious code can be written and executed before the process' entry point (and potentially subsequent anti-malware hooks) via an APC. AtomBombing is another variation that utilizes APCs to invoke malicious code previously written to the global atom table.
Running code in the context of another process may allow access to the process's memory, system/network resources, and possibly elevated privileges. Execution via APC injection may also evade detection from security products since the execution is masked under a legitimate process.
Rules on DetectionCode tagged with T1055.004.
| Rule | Type | Risk | Data source |
|---|---|---|---|
| PowerShell PInvoke Process Injection API Chain | TTP | NULL | Powershell Script Block Logging 4104 |
None recorded.
| Used by | Procedure example |
|---|---|
| MalwareAttor | Attor performs the injection by attaching its code into the APC queue using NtQueueApcThread API. |
| MalwareBADHATCH | BADHATCH can inject itself into a new `svchost.exe -k netsvcs` process using the asynchronous procedure call (APC) queue. |
| MalwareBumblebee | Bumblebee can use asynchronous procedure call (APC) injection to execute commands received from C2. |
| MalwareCarberp | Carberp has queued an APC routine to explorer.exe by calling ZwQueueApcThread. |
| MalwareHeartCrypt | HeartCrypt has the ability to use `NtQueueApcThread` as an alternate method for process injection. |
| MalwareIcedID | IcedID has used |
| MalwareInvisiMole | InvisiMole can inject its code into a trusted process via the APC queue. |
| MalwarePillowmint | Pillowmint has used the NtQueueApcThread syscall to inject code into svchost.exe. |
Data from MITRE ATT&CK® (Enterprise). ATT&CK® is a registered trademark of The MITRE Corporation.
