Ptrace System Calls - T1055.008 (ea016b56-ae0e-47fe-967a-cc0ad51af67f)
Adversaries may inject malicious code into processes via ptrace (process trace) system calls in order to evade process-based defenses as well as possibly elevate privileges. Ptrace system call injection is a method of executing arbitrary code in the address space of a separate live process.
Ptrace system call injection involves attaching to and modifying a running process. The ptrace system call enables a debugging process to observe and control another process (and each individual thread), including changing memory and register values.(Citation: PTRACE man) Ptrace system call injection is commonly performed by writing arbitrary code into a running process (ex: malloc) then invoking that memory with PTRACE_SETREGS to set the register containing the next instruction to execute. Ptrace system call injection can also be done with PTRACE_POKETEXT/PTRACE_POKEDATA, which copy data to a specific address in the target processes’ memory (ex: the current address of the next instruction). (Citation: PTRACE man)(Citation: Medium Ptrace JUL 2018)
Ptrace system call injection may not be possible targeting processes that are non-child processes and/or have higher-privileges.(Citation: BH Linux Inject)
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 ptrace system call injection may also evade detection from security products since the execution is masked under a legitimate process.
| Cluster A | Galaxy A | Cluster B | Galaxy B | Level |
|---|---|---|---|---|
| Process Injection - T1055 (43e7dc91-05b2-474c-b9ac-2ed4fe101f4d) | Attack Pattern | Ptrace System Calls - T1055.008 (ea016b56-ae0e-47fe-967a-cc0ad51af67f) | Attack Pattern | 1 |