S0132: H1N1

H1N1 is a malware variant that has been distributed via a campaign using VBA macros to infect victims. Although it initially had only loader capabilities, it has evolved to include information-stealing functionality. [1]

EnterpriseS0132MalwareObject v1.2 Modified May 12, 2026, 15:12 UTC (UTC+00:00)

H1N1 matters because ATT&CK describes it as Windows malware delivered through VBA macros that evolved from a loader into information-stealing capability. For leaders, the practical issue is not just one malware name; it is whether the organization can see and contain a Windows intrusion path that may involve macro-enabled content, obfuscated or packed payloads, command-shell execution, credential theft from browsers, lateral spread through shared content or removable media, and concealed command-and-control traffic.

Executive priority

Treat H1N1 as a validation case for endpoint, email/document handling, credential protection, and incident response readiness on Windows. Priority questions: are macro-delivered payloads controlled and logged; can the SOC correlate command shell, file transfer, browser credential access, UAC bypass, firewall modification, and encoded/encrypted outbound traffic; and can IR teams preserve evidence quickly if security tooling, recovery features, or host firewall settings are modified. This supports budget and audit discussions around endpoint visibility, least privilege, removable media governance, backup/recovery assurance, and control evidence for malware prevention and response.

Technical view

MITRE does not provide official detection text for H1N1, so defenders should build coverage from the supplied behavior relationships. Validate Windows telemetry for VBA macro-originated process chains, packed or obfuscated files, cmd.exe execution, ingress tool transfer, browser credential store access, UAC bypass behavior, tainted shared locations, removable media replication, encoded or symmetrically encrypted C2-like communications, Windows host firewall changes, and potential impairment of security or recovery mechanisms. Because several related techniques list non-Windows platforms while the malware object itself is Windows, prioritize Windows-relevant evidence and document where ATT&CK relationship context requires local confirmation.

Likely telemetry

Email gateway and endpoint evidence for macro-enabled Office documents and child-process execution from document applications
Windows process creation telemetry, especially command shell execution and suspicious parent-child process chains
Endpoint file telemetry for packed, encoded, encrypted, newly dropped, or renamed executables
Network telemetry for external file transfer and encoded or encrypted command-and-control-like traffic patterns
Browser credential store access, file reads, or process access events where available

Detection direction

Do not rely on a malware signature alone; tune detections around behavior clusters such as macro-to-shell execution, dropped packed payloads, outbound transfer, and credential-store access.
Correlate endpoint and network signals because data encoding and symmetric cryptography can reduce content-based network visibility.
Baseline legitimate administrative use of cmd.exe, firewall changes, removable media, and shared-drive writes to reduce false positives while preserving high-risk combinations.
Validate visibility on shared storage and removable media, which are common blind spots for lateral movement and initial access scenarios.
Review whether EDR, logging, and recovery-control tampering alerts are collected centrally before a host becomes unavailable or evidence is altered.

Mitigation priorities

Reduce macro-delivered malware risk through controlled macro policy, document-handling safeguards, and user-facing reporting paths for suspicious files.
Harden Windows endpoints with least privilege, controlled elevation, and monitoring of UAC bypass-related behavior.
Protect credentials by limiting browser password storage where appropriate, enforcing strong identity controls, and monitoring access to browser credential stores.
Restrict and monitor removable media and shared content locations, especially where they bridge operational, sensitive, or less-managed systems.
Ensure endpoint security, logging agents, host firewall policy, and recovery controls are centrally managed and monitored for unauthorized change.

Analyst notes and limits

The object is a malware entry, not a technique, and the supplied ATT&CK record has no tactics and no official detection section. The strongest source-supported points are Windows platform scope, VBA macro distribution, evolution from loader to information stealing, and the listed technique relationships. Relationship-driven items such as recovery inhibition or tool impairment should be treated as coverage validation prompts rather than assumptions about every H1N1 incident.

This take uses only the provided ATT&CK fields, external references, and relationships. It does not establish current activity, attribution, prevalence, affected customers, or guaranteed detections. Local telemetry, sample analysis, control configuration, and incident evidence are required to determine actual exposure and coverage.

Official MITRE ATT&CK definition

H1N1

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 techniques 13 rows

Domain	ID	Name	Relationship / procedure
Enterprise	T1555.003	Credentials from Web Browsers Sub-technique	H1N1 dumps usernames and passwords from Firefox, Internet Explorer, and Outlook.CitationCisco H1N1 Part 2
Enterprise	T1080	Taint Shared Content	H1N1 has functionality to copy itself to network shares.CitationCisco H1N1 Part 2
Enterprise	T1490	Inhibit System Recovery	H1N1 disable recovery options and deletes shadow copies from the victim.CitationCisco H1N1 Part 2
Enterprise	T1027	Obfuscated Files or Information	H1N1 uses multiple techniques to obfuscate strings, including XOR.CitationCisco H1N1 Part 1
Enterprise	T1059.003	Windows Command Shell Sub-technique	H1N1 kills and disables services by using cmd.exe.CitationCisco H1N1 Part 2
Enterprise	T1091	Replication Through Removable Media	H1N1 has functionality to copy itself to removable media.CitationCisco H1N1 Part 2
Enterprise	T1686.003	Windows Host Firewall Sub-technique	H1N1 kills and disables services for Windows Firewall.CitationCisco H1N1 Part 2
Enterprise	T1548.002	Bypass User Account Control Sub-technique	H1N1 bypasses user access control by using a DLL hijacking vulnerability in the Windows Update Standalone Installer (wusa.exe).CitationCisco H1N1 Part 2
Enterprise	T1027.002	Software Packing Sub-technique	H1N1 uses a custom packing algorithm.CitationCisco H1N1 Part 1
Enterprise	T1105	Ingress Tool Transfer	H1N1 contains a command to download and execute a file from a remotely hosted URL using WinINet HTTP requests.CitationCisco H1N1 Part 2
Enterprise	T1132	Data Encoding	H1N1 obfuscates C2 traffic with an altered version of base64.CitationCisco H1N1 Part 2
Enterprise	T1573.001	Symmetric Cryptography Sub-technique	H1N1 encrypts C2 traffic using an RC4 key.CitationCisco H1N1 Part 2
Enterprise	T1685	Disable or Modify Tools	H1N1 kills and disables services for Windows Security Center, and Windows Defender.CitationCisco H1N1 Part 2

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: 19.1
Object version: 1.2
Created: May 31, 2017, 21:33 UTC (UTC+00:00)
Modified: May 12, 2026, 15:12 UTC (UTC+00:00)
Raw hash: ab052b809b822866...

Imported snapshots across ATT&CK releases (1)

Release	Bundle imported	Object version	Modified	Status	Raw hash
19.1	May 18, 2026, 07:08 UTC (UTC+00:00)	1.2	May 12, 2026, 15:12 UTC (UTC+00:00)	Current bundle	`ab052b809b82…`

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]
Cisco H1N1 Part 1

Reynolds, J.. (2016, September 13). H1N1: Technical analysis reveals new capabilities. Retrieved September 26, 2016.
Open source URL
[2]
mitre-attack S0132
Open source URL

Source and licensing

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