T1055.008 Ptrace System Calls

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: <code>malloc</code>) then invoking that memory with <code>PTRACE_SETREGS</code> to set the register containing the next instruction to execute. Ptrace system call injection can also be done with <code>PTRACE_POKETEXT</code>/<code>PTRACE_POKEDATA</code>, 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.

View in MITRE ATT&CK®

CRI Profile Mappings

Capability ID Capability Description Mapping Type ATT&CK ID ATT&CK Name Notes
PR.PS-05.02 Mobile code prevention Mitigates T1055.008 Ptrace System Calls
Comments
Mobile code procedures address specific actions taken to prevent the development, acquisition, and introduction of unacceptable mobile code within organizational systems, including requiring mobile code to be digitally signed by a trusted source.
References
    PR.AA-05.02 Privileged system access Mitigates T1055.008 Ptrace System Calls
    Comments
    This diagnostic statement protects against Ptrace System Calls through the use of privileged account management and the use of multi-factor authentication.
    References

      Azure Mappings

      Capability ID Capability Description Mapping Type ATT&CK ID ATT&CK Name Notes
      defender_for_app_service Microsoft Defender for Cloud: Defender for App Service technique_scores T1055.008 Ptrace System Calls
      Comments
      Injection attacks are specifically cited as a detection focus for Fileless Attack Detection, which is part of this control, with even more specific references to Process Hollowing, executable image injection, and threads started in a dynamically allocated code segment. Detection is periodic at an unknown rate.
      References