S0187: Daserf

Daserf is a backdoor that has been used to spy on and steal from Japanese, South Korean, Russian, Singaporean, and Chinese victims. Researchers have identified versions written in both Visual C and Delphi. [1] [2]

EnterpriseS0187MalwareObject v1.1ModifiedApr 25, 2025, 14:44 UTC (UTC+00:00)

S0187: Daserf describes [Daserf](https://attack.mitre.org/software/S0187) is a backdoor that has been used to spy on and steal from Japanese, South Korean, Russian, Singaporean, and Chinese victims. Researchers have identified versions written in both Visual C and Delphi. (Citation: Trend Micro Daserf Nov 2017) (Citation: Secureworks BRONZE BUTLER Oct 2017)

Executive priority

S0187: Daserf 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 S0187: Daserf 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 S0187: Daserf 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

Daserf

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 techniques16 rows

Domain	ID	Name	Relationship / procedure
Enterprise	T1059.003	Windows Command ShellSub-technique	Daserf can execute shell commands.[1][2]
Enterprise	T1553.002	Code SigningSub-technique	Some Daserf samples were signed with a stolen digital certificate.CitationSymantec Tick Apr 2016
Enterprise	T1105	Ingress Tool Transfer	Daserf can download remote files.[1][2]
Enterprise	T1027.002	Software PackingSub-technique	A version of Daserf uses the MPRESS packer.[1]
Enterprise	T1132.001	Standard EncodingSub-technique	Daserf uses custom base64 encoding to obfuscate HTTP traffic.[2]
Enterprise	T1560.001	Archive via UtilitySub-technique	Daserf hides collected data in password-protected .rar archives.CitationSymantec Tick Apr 2016
Enterprise	T1113	Screen Capture	Daserf can take screenshots.[1][2]
Enterprise	T1027	Obfuscated Files or Information	Daserf uses encrypted Windows APIs and also encrypts data using the alternative base64+RC4 or the Caesar cipher.[1]
Enterprise	T1573.001	Symmetric CryptographySub-technique	Daserf uses RC4 encryption to obfuscate HTTP traffic.[2]
Enterprise	T1036.005	Match Legitimate Resource Name or LocationSub-technique	Daserf uses file and folder names related to legitimate programs in order to blend in, such as HP, Intel, Adobe, and perflogs.CitationSymantec Tick Apr 2016
Enterprise	T1056.001	KeyloggingSub-technique	Daserf can log keystrokes.[1][2]
Enterprise	T1071.001	Web ProtocolsSub-technique	Daserf uses HTTP for C2.[2]
Enterprise	T1003.001	LSASS MemorySub-technique	Daserf leverages Mimikatz and Windows Credential Editor to steal credentials.CitationSymantec Tick Apr 2016
Enterprise	T1560	Archive Collected Data	Daserf hides collected data in password-protected .rar archives.CitationSymantec Tick Apr 2016
Enterprise	T1027.005	Indicator Removal from ToolsSub-technique	Analysis of Daserf has shown that it regularly undergoes technical improvements to evade anti-virus detection.[1]
Enterprise	T1001.002	SteganographySub-technique	Daserf can use steganography to hide malicious code downloaded to the victim.[1]

Associated objects

Groups, software, and campaigns

G0060: BRONZE BUTLER

BRONZE BUTLER is a cyber espionage group with likely Chinese origins that has been active since at least 2008. The group primarily targets Japanese organizations, particularly those in government, biotechnology, electronics manufacturing, and industrial chemistry.[1][2][3]

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: 1.1
Created: Jan 16, 2018, 16:13 UTC (UTC+00:00)
Modified: Apr 25, 2025, 14:44 UTC (UTC+00:00)
Raw hash: 0298ca1bc71dcd71...

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)	1.1	Apr 25, 2025, 14:44 UTC (UTC+00:00)	Current bundle	`0298ca1bc71d…`
19.1	Jul 14, 2026, 09:14 UTC (UTC+00:00)	1.1	Apr 25, 2025, 14:44 UTC (UTC+00:00)	Older bundle	`0298ca1bc71d…`

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]
Trend Micro Daserf Nov 2017
Chen, J. and Hsieh, M. (2017, November 7). REDBALDKNIGHT/BRONZE BUTLER’s Daserf Backdoor Now Using Steganography. Retrieved December 27, 2017.
[2]
Secureworks BRONZE BUTLER Oct 2017
Counter Threat Unit Research Team. (2017, October 12). BRONZE BUTLER Targets Japanese Enterprises. Retrieved January 4, 2018.
Open source URL
[3]
Daserf
(Citation: Trend Micro Daserf Nov 2017)
[4]
Muirim
(Citation: Trend Micro Daserf Nov 2017)
[5]
Nioupale
(Citation: Trend Micro Daserf Nov 2017)
[6]
mitre-attackS0187
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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