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MITRE ATT&CK® Technique

T1055.005: Thread Local Storage

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.[1]

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.

EnterpriseT1055.005Sub-techniqueObject v2.0Modified
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Glexia's Take · Automated analysis

Security context for executives and security teams

Automation confidenceMedium

T1055.005: Thread Local Storage describes 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...

Executive priority

T1055.005: Thread Local Storage is an official MITRE ATT&CK technique. Glexia treats it as defensive behavior context for prioritizing monitoring, control validation, and response planning without using the object by itself as an attribution claim.

Technical view

Security teams should validate T1055.005: Thread Local Storage by reviewing the official ATT&CK relationships, mapped tactics (stealth, privilege-escalation), supported platforms (Windows), and available local telemetry before making detection or mitigation decisions.

Likely telemetry

  • Official ATT&CK relationships and object metadata
  • Identity, privilege, and authentication events
  • Network, endpoint, and security-tool telemetry

Detection direction

  • Validate whether T1055.005: Thread Local Storage appears in your detection coverage and tabletop scenarios.
  • Use the object to align executive risk language with SOC, incident response, and detection engineering work.
  • Do not treat ATT&CK relationship context as attribution without corroborating evidence.

Mitigation priorities

  • Map the object to existing controls and identify missing telemetry or response ownership.
  • Prioritize mitigations that reduce exposure on the listed platforms and tactics.
  • Review adjacent ATT&CK relationships before changing policy, detections, or reporting language.
Additional notes and limits

Baseline Glexia take generated from the official MITRE ATT&CK STIX object, source hash, tactics, platforms, and detection fields. It is safe to replace with a richer model-generated take for the same source hash later.

This baseline take is source-grounded and schema-validated, but it does not include environment-specific telemetry, incident evidence, or threat-intelligence corroboration.

Generated from the cited source records. This long-tail analysis has not been individually reviewed by a named human.

Official MITRE ATT&CK definition

Thread Local Storage

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.[1]

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 the same entry on attack.mitre.org (MITRE-hosted reference; in-page links above use the Glexia ATT&CK library.)

Glexia analysis

How security teams should use this page

Treat this object as behavior context, not an attribution claim. Validate the related groups, software, data sources, and mitigations against official ATT&CK relationships and your own telemetry before making control-coverage decisions.

ATT&CK relationship table

Related techniques

This mirrors the MITRE pattern of making group, software, campaign, and technique relationships scannable. Relationship notes come from mirrored ATT&CK relationship text when available.

1 rows
DomainIDNameRelationship / procedure
EnterpriseT1055Process InjectionThis object subtechnique of Process Injection.
Associated objects

Groups, software, and campaigns

MalwareEnterprise

S0386: Ursnif

Ursnif is a banking trojan and variant of the Gozi malware observed being spread through various automated exploit kits, Spearphishing Attachments, and malicious links.[1][2] Ursnif is associated primarily with data theft, but variants also include components (backdoors, spyware, file injectors, etc.) capable of a wide variety of behaviors.[3]

Windows
MalwareEnterprise

S1237: CANONSTAGER

CANONSTAGER is a loader known to be leveraged by Mustang Panda and was first observed utilized in 2025. Mustang Panda utilizes DLL side-loading to execute within the victim environment prior to delivering a follow-on malicious encrypted payload. CANONSTAGER leverages Thread Local Storage (TLS) and Native Windows APIs within the victim environment to elude detections. CANONSTAGER also hides its code utilizing window procedures and message queues.[1]

Windows
Relationship explorer

All related ATT&CK context

mitigates · MitigationM1040: Behavior Prevention on EndpointEnterpriseuses · MalwareS0386: UrsnifEnterpriseuses · MalwareS1237: CANONSTAGEREnterprisesubtechnique of · TechniqueT1055: Process InjectionEnterprisedetects · Detection StrategyDET0467: Detection Strategy for TLS Callback Injection via PE Memory Modification and HollowingEnterprise
Mitigations

Mitigation direction

MitigationEnterprise

M1040: Behavior Prevention on Endpoint

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.

Change history

Object version and sync metadata

The fields below describe the current mirrored snapshot. When Glexia retains multiple ATT&CK source imports, you can open the table to compare the same object across releases (hashes and MITRE timestamps). For MITRE’s own release notes and roadmap, see ATT&CK resources — Updates.

ATT&CK release
19.2
Object version
2.0
Created
Modified
Raw hash
f0fac5f5e986809e...
Imported snapshots across ATT&CK releases(2)
ReleaseBundle importedObject versionModifiedStatusRaw hash
19.22.0Current bundlef0fac5f5e986…
19.12.0Older bundlef0fac5f5e986…
Raw source

Mirrored ATT&CK source object

The raw object is retained through the mirrored ATT&CK source bundle and object hash. The raw endpoint returns the exact object from the mirrored bundle when available.

Open mirrored raw JSONOpen MITRE-hosted copy
Source references

External references and citations

MITRE external references are preserved separately from Glexia analysis so citations remain traceable to their original source records.

  1. [1]
    FireEye TLS Nov 2017

    Vaish, A. & Nemes, S. (2017, November 28). Newly Observed Ursnif Variant Employs Malicious TLS Callback Technique to Achieve Process Injection. Retrieved December 18, 2017.

    Open source URL
  2. [2]
    mitre-attackT1055.005
    Open source URL
Source and licensing

Source: MITRE ATT&CK®. © 2026 The MITRE Corporation. This work is reproduced and distributed with the permission of The MITRE Corporation. MITRE ATT&CK and ATT&CK are registered trademarks of The MITRE Corporation. Glexia is not affiliated with or endorsed by MITRE.

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