T1055: Process Injection

ATT&CK Mapping

Field	Value
Technique ID	T1055
Name	Process Injection
Tactic	stealth (stealth)
Platforms	Linux, macOS, Windows
Sub-technique	No

Why it matters

In the OpenTrojan knowledge graph, Process Injection (T1055) is one of the highest-connectivity ATT&CK techniques: 87 MITRE STIX relationships reference this technique; 15 threat groups observed using it; 65 software families associated; 7 campaigns associated; 5 OpenTrojan content pages reference it. These counts are derived from MITRE ATT&CK STIX relationships and are not an estimate of exploitation volume.

How attackers use it

Behavior described below is from the MITRE ATT&CK canonical definition (source: https://attack.mitre.org/techniques/T1055). Adversaries may inject code into processes in order to evade process-based defenses as well as possibly elevate privileges. Process injection is a method of executing arbitrary code in the address space of a separate live process. 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 process injection may also evade detection from security products since the execution is masked under a legitimate process. There are many different ways to inject code into a process, many of which abuse legitimate functionalities. These implementations exist for every major OS but are typically platform specific. More sophisticated samples may perform multiple process injections to segment modules and further evade detection, utilizing named pipes or other inter-process communication (IPC) mechanisms as a communication channel.

Detection

DET0508 Behavioral Detection of Process Injection Across Platforms AN1399 Detects process injection by correlating memory manipulation API calls (e.g., VirtualAllocEx, WriteProcessMemory), suspicious thread creation (e.g., CreateRemoteThread), and unusual DLL loads within another process’s context. AN1400 Detects ptrace- or memfd-based process injection through audit logs capturing system calls (e.g., ptrace, mmap) targeting running processes along with suspicious file descriptors or memory writes. AN1401 Detects memory-based injection by monitoring task_for_pid , mach_vm_write , and dylib injection patterns through DYLD_INSERT_LIBRARIES or manual memory mapping.

Detection strategy text is from the MITRE ATT&CK official technique page (https://attack.mitre.org/techniques/T1055).

Mitigation

Behavior Prevention on Endpoint refers to the use of technologies and strategies to detect and block potentially malicious activities by analyzing the behavior of processes, files, API calls, and other endpoint events. Rather than relying solely on known signatures, this approach leverages heuristics, machine learning, and real-time monitoring to identify anomalous patterns indicative of an attack. This mitigation can be implemented through the following measures:

Suspicious Process Behavior:

• Implementation: Use Endpoint Detection and Response (EDR) tools to monitor and block processes exhibiting unusual behavior, such as privilege escalation attempts.
• Use Case: An attacker uses a known vulnerability to spawn a privileged process from a user-level application. The endpoint tool detects the abnormal parent-child process relationship and blocks the action.

Unauthorized File Access:

• Implementation: Leverage Data Loss Prevention (DLP) or endpoint tools to block processes attempting to access sensitive files without proper authorization.
• Use Case: A process tries to read or modify a sensitive file located in a restricted directory, such as /etc/shadow on Linux or the SAM registry hive on Windows. The endpoint tool identifies this anomalous behavior and prevents it.

Abnormal API Calls:

• Implementation: Implement runtime analysis tools to monitor API calls and block those associated with malicious activities.
• Use Case: A process dynamically injects itself into another process to hijack its execution. The endpoint detects the abnormal use of APIs like OpenProcess and WriteProcessMemory and terminates the offending process.

Exploit Prevention:

• Implementation: Use behavioral exploit prevention tools to detect and block exploits attempting to gain unauthorized access.
• Use Case: A buffer overflow exploit is launched against a vulnerable application. The endpoint detects the anomalous memory write operation and halts the process.

Mitigation guidance is from the MITRE ATT&CK course-of-action associated with this technique.

Related Software

• TrickBot
• Ninja
• Wiarp
• Bumblebee
• Backdoor.Oldrea
• COATHANGER
• Smoke Loader
• AuditCred
• NETWIRE
• DUSTTRAP
• BADHATCH
• Avenger

Software associations are from MITRE ATT&CK STIX relationships (observed usage, not attribution).

Related Threat Groups

• APT38
• BlackByte
• Kimsuky
• APT41
• APT32
• Gamaredon Group
• TA2541
• APT37
• Turla
• APT5
• Silence
• Cobalt Group

Group associations are from MITRE ATT&CK STIX relationships.

Related Campaigns

• RedPenguin
• Operation Sharpshooter
• 2015 Ukraine Electric Power Attack
• 3CX Supply Chain Attack
• Cutting Edge
• ArcaneDoor
• Operation Wocao

Campaign associations are from MITRE ATT&CK STIX relationships.

Related Content

• APT25
• APT32
• Equation Group
• FIN7
• Turla

References

• https://attack.mitre.org/techniques/T1055