T1055.005 Thread Local Storage Mappings

Adversaries may inject malicious code into processes via thread local storage (TLS) callbacks in order to evade process-based defenses as well as possibly elevate privileges. TLS callback injection is a method of executing arbitrary code in the address space of a separate live process.

TLS callback injection involves manipulating pointers inside a portable executable (PE) to redirect a process to malicious code before reaching the code's legitimate entry point. TLS callbacks are normally used by the OS to setup and/or cleanup data used by threads. Manipulating TLS callbacks may be performed by allocating and writing to specific offsets within a process’ memory space using other Process Injection techniques such as Process Hollowing.(Citation: FireEye TLS Nov 2017)

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 TLS callback injection may also evade detection from security products since the execution is masked under a legitimate process.

View in MITRE ATT&CK®

Mappings

Capability ID Capability Description Mapping Type ATT&CK ID ATT&CK Name
AC-6 Least Privilege Protects T1055.005 Thread Local Storage
SC-18 Mobile Code Protects T1055.005 Thread Local Storage
SC-7 Boundary Protection Protects T1055.005 Thread Local Storage
SI-2 Flaw Remediation Protects T1055.005 Thread Local Storage
SI-3 Malicious Code Protection Protects T1055.005 Thread Local Storage
SI-4 System Monitoring Protects T1055.005 Thread Local Storage
action.malware.variety.In-memory (malware never stored to persistent storage) related-to T1055.005 Process Injection: Thread Local Storage