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MITRE ATT&CK® Malware

S1105: COATHANGER

COATHANGER is a remote access tool (RAT) targeting FortiGate networking appliances. First used in 2023 in targeted intrusions against military and government entities in the Netherlands along with other victims, COATHANGER was disclosed in early 2024, with a high confidence assessment linking this malware to a state-sponsored entity in the People's Republic of China. COATHANGER is delivered after gaining access to a FortiGate device, with in-the-wild observations linked to exploitation of CVE-2022-42475. The name COATHANGER is based on a unique string in the malware used to encrypt configuration files on disk: “She took his coat and hung it up”.[1]

EnterpriseS1105MalwareObject v1.1Modified
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Glexia's Take · Automated analysis

Security context for executives and security teams

Automation confidenceMedium

S1105: COATHANGER describes [COATHANGER](https://attack.mitre.org/software/S1105) is a remote access tool (RAT) targeting FortiGate networking appliances. First used in 2023 in targeted intrusions against military and government entities in the Netherlands along with other victims, [COATHANGER](https://attack.mitre.org/software/S1105) was disclosed in early 2024, with a high confidence assessment linking this malware to a state-sponsored entity in the People's Republic of China. [COATHANGER](https://attack.mitre.org/software/S1105) is deliver...

Executive priority

S1105: COATHANGER is an official MITRE ATT&CK software. 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 S1105: COATHANGER by reviewing the official ATT&CK relationships, mapped tactics (the mapped ATT&CK tactic context), supported platforms (Linux, Network Devices), and available local telemetry before making detection or mitigation decisions.

Likely telemetry

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

Detection direction

  • Validate whether S1105: COATHANGER 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

COATHANGER

COATHANGER is a remote access tool (RAT) targeting FortiGate networking appliances. First used in 2023 in targeted intrusions against military and government entities in the Netherlands along with other victims, COATHANGER was disclosed in early 2024, with a high confidence assessment linking this malware to a state-sponsored entity in the People's Republic of China. COATHANGER is delivered after gaining access to a FortiGate device, with in-the-wild observations linked to exploitation of CVE-2022-42475. The name COATHANGER is based on a unique string in the malware used to encrypt configuration files on disk: “She took his coat and hung it up”.[1]

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

Techniques used

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.

18 rows
DomainIDNameRelationship / procedure
EnterpriseT1070.004File DeletionSub-technique

COATHANGER removes files from victim environments following use in multiple instances.[1]

EnterpriseT1095Non-Application Layer Protocol

COATHANGER uses ICMP for transmitting configuration information to and from its command and control server.[1]

EnterpriseT1057Process Discovery

COATHANGER will query running process information to determine subsequent program execution flow.[1]

EnterpriseT1543.004Launch DaemonSub-technique

COATHANGER will create a daemon for timed check-ins with command and control infrastructure.[1]

EnterpriseT1055Process Injection

COATHANGER includes a binary labeled `authd` that can inject a library into a running process and then hook an existing function within that process with a new function from that library.[1]

EnterpriseT1059.004Unix ShellSub-technique

COATHANGER provides a BusyBox reverse shell for command and control.[1]

EnterpriseT1190Exploit Public-Facing Application

COATHANGER is installed following exploitation of a vulnerable FortiGate device. [1]

EnterpriseT1222.002Linux and Mac PermissionsSub-technique

COATHANGER will set the GID of `httpsd` to 90 when infected.[1]

EnterpriseT1083File and Directory Discovery

COATHANGER will survey the contents of system files during installation.[1]

EnterpriseT1014Rootkit

COATHANGER hooks or replaces multiple legitimate processes and other functions on victim devices.[1]

EnterpriseT1574.006Dynamic Linker HijackingSub-technique

COATHANGER copies the malicious file /data2/.bd.key/preload.so to /lib/preload.so, then launches a child process that executes the malicious file /data2/.bd.key/authd as /bin/authd with the arguments /lib/preload.so reboot newreboot 1.[1] This injects the malicious preload.so file into the process with PID 1, and replaces its reboot function with the malicious newreboot function for persistence.

EnterpriseT1027.002Software PackingSub-technique

The first stage of COATHANGER is delivered as a packed file.[1]

EnterpriseT1573.002Asymmetric CryptographySub-technique

COATHANGER connects to command and control infrastructure using SSL.[1]

EnterpriseT1574Hijack Execution Flow

COATHANGER will remove and write malicious shared objects associated with legitimate system functions such as `read(2)`.[1]

EnterpriseT1071.001Web ProtocolsSub-technique

COATHANGER uses an HTTP GET request to initialize a follow-on TLS tunnel for command and control.[1]

EnterpriseT1140Deobfuscate/Decode Files or Information

COATHANGER decodes configuration items from a bundled file for command and control activity.[1]

EnterpriseT1564.001Hidden Files and DirectoriesSub-technique

COATHANGER creates and installs itself to a hidden installation directory.[1]

EnterpriseT1027Obfuscated Files or Information

COATHANGER can store obfuscated configuration information in the last 56 bytes of the file `/date/.bd.key/preload.so`.[1]

Relationship explorer

All related ATT&CK context

uses · TechniqueT1070.004: File DeletionEnterpriseuses · TechniqueT1095: Non-Application Layer ProtocolEnterpriseuses · TechniqueT1057: Process DiscoveryEnterpriseuses · TechniqueT1543.004: Launch DaemonEnterpriseuses · TechniqueT1055: Process InjectionEnterpriseuses · TechniqueT1059.004: Unix ShellEnterpriseuses · TechniqueT1190: Exploit Public-Facing ApplicationEnterpriseuses · TechniqueT1222.002: Linux and Mac PermissionsEnterpriseuses · TechniqueT1083: File and Directory DiscoveryEnterpriseuses · TechniqueT1014: RootkitEnterpriseuses · TechniqueT1574.006: Dynamic Linker HijackingEnterpriseuses · TechniqueT1027.002: Software PackingEnterpriseuses · TechniqueT1573.002: Asymmetric CryptographyEnterpriseuses · TechniqueT1574: Hijack Execution FlowEnterpriseuses · TechniqueT1071.001: Web ProtocolsEnterpriseuses · TechniqueT1140: Deobfuscate/Decode Files or InformationEnterpriseuses · TechniqueT1564.001: Hidden Files and DirectoriesEnterpriseuses · TechniqueT1027: Obfuscated Files or InformationEnterprise
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
20.0
Object version
1.1
Created
Modified
Raw hash
f8843ffffdffcabb...
Imported snapshots across ATT&CK releases(3)
ReleaseBundle importedObject versionModifiedStatusRaw hash
20.01.1Current bundlef8843ffffdff…
19.21.1Older bundlef8843ffffdff…
19.11.1Older bundlef8843ffffdff…
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]
    NCSC-NL COATHANGER Feb 2024

    Dutch Military Intelligence and Security Service (MIVD) & Dutch General Intelligence and Security Service (AIVD). (2024, February 6). Ministry of Defense of the Netherlands uncovers COATHANGER, a stealthy Chinese FortiGate RAT. Retrieved February 7, 2024.

    Open source URL
  2. [2]
    mitre-attackS1105
    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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