S0256: Mosquito

Mosquito is a Win32 backdoor that has been used by Turla. Mosquito is made up of three parts: the installer, the launcher, and the backdoor. The main backdoor is called CommanderDLL and is launched by the loader program. [1]

EnterpriseS0256MalwareObject v1.3ModifiedApr 11, 2024, 00:38 UTC (UTC+00:00)

S0256: Mosquito describes [Mosquito](https://attack.mitre.org/software/S0256) is a Win32 backdoor that has been used by [Turla](https://attack.mitre.org/groups/G0010). [Mosquito](https://attack.mitre.org/software/S0256) is made up of three parts: the installer, the launcher, and the backdoor. The main backdoor is called CommanderDLL and is launched by the loader program. (Citation: ESET Turla Mosquito Jan 2018)

Executive priority

S0256: Mosquito 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 S0256: Mosquito by reviewing the official ATT&CK relationships, mapped tactics (the mapped ATT&CK tactic context), supported platforms (Windows), 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 S0256: Mosquito 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

Mosquito

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.

Filter related techniques17 rows

Domain	ID	Name	Relationship / procedure
Enterprise	T1047	Windows Management Instrumentation	Mosquito's installer uses WMI to search for antivirus display names.[1]
Enterprise	T1033	System Owner/User Discovery	Mosquito runs `whoami` on the victim’s machine.[1]
Enterprise	T1218.011	Rundll32Sub-technique	Mosquito's launcher uses rundll32.exe in a Registry Key value to start the main backdoor capability.[1]
Enterprise	T1070.004	File DeletionSub-technique	Mosquito deletes files using DeleteFileW API call.[1]
Enterprise	T1573.001	Symmetric CryptographySub-technique	Mosquito uses a custom encryption algorithm, which consists of XOR and a stream that is similar to the Blum Blum Shub algorithm.[1]
Enterprise	T1518.001	Security Software DiscoverySub-technique	Mosquito's installer searches the Registry and system to see if specific antivirus tools are installed on the system.[1]
Enterprise	T1059.001	PowerShellSub-technique	Mosquito can launch PowerShell Scripts.[1]
Enterprise	T1112	Modify Registry	Mosquito can modify Registry keys under `HKCU\Software\Microsoft\[dllname]` to store configuration values. Mosquito also modifies Registry keys under `HKCR\CLSID\...\InprocServer32` with a path to the launcher.[1]
Enterprise	T1105	Ingress Tool Transfer	Mosquito can upload and download files to the victim.[1]
Enterprise	T1546.015	Component Object Model HijackingSub-technique	Mosquito uses COM hijacking as a method of persistence.[1]
Enterprise	T1027.013	Encrypted/Encoded FileSub-technique	Mosquito’s installer is obfuscated with a custom crypter to obfuscate the installer.[1]
Enterprise	T1057	Process Discovery	Mosquito runs `tasklist` to obtain running processes.[1]
Enterprise	T1016	System Network Configuration Discovery	Mosquito uses the `ipconfig` command.[1]
Enterprise	T1059.003	Windows Command ShellSub-technique	Mosquito executes cmd.exe and uses a pipe to read the results and send back the output to the C2 server.[1]
Enterprise	T1547.001	Registry Run Keys / Startup FolderSub-technique	Mosquito establishes persistence under the Registry key `HKCU\Software\Run auto_update`.[1]
Enterprise	T1106	Native API	Mosquito leverages the CreateProcess() and LoadLibrary() calls to execute files with the .dll and .exe extensions.[1]
Enterprise	T1027.011	Fileless StorageSub-technique	Mosquito stores configuration values under the Registry key `HKCU\Software\Microsoft\[dllname]`.[1]

Associated objects

Groups, software, and campaigns

G0010: Turla

Turla is a cyber espionage threat group that has been attributed to Russia's Federal Security Service (FSB). They have compromised victims in over 50 countries since at least 2004, spanning a range of industries including government, embassies, military, education, research and pharmaceutical companies. Turla is known for conducting watering hole and spearphishing campaigns, and leveraging in-house tools and malware, such as Uroburos.[1][2][3][4][5]

Relationship explorer

All related ATT&CK context

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: 1.3
Created: Oct 17, 2018, 00:14 UTC (UTC+00:00)
Modified: Apr 11, 2024, 00:38 UTC (UTC+00:00)
Raw hash: 03bfe8ab6bb082f2...

Imported snapshots across ATT&CK releases(2)

Release	Bundle imported	Object version	Modified	Status	Raw hash
19.2	Aug 6, 2026, 02:58 UTC (UTC+00:00)	1.3	Apr 11, 2024, 00:38 UTC (UTC+00:00)	Current bundle	`03bfe8ab6bb0…`
19.1	Jul 14, 2026, 09:14 UTC (UTC+00:00)	1.3	Apr 11, 2024, 00:38 UTC (UTC+00:00)	Older bundle	`03bfe8ab6bb0…`

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 JSON Open 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]
ESET Turla Mosquito Jan 2018
ESET, et al. (2018, January). Diplomats in Eastern Europe bitten by a Turla mosquito. Retrieved July 3, 2018.
Open source URL
[2]
Mosquito
(Citation: ESET Turla Mosquito Jan 2018)
[3]
mitre-attackS0256
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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