Hyperbro

Category: trojan · Aliases: APT.HyperBro, Backdoor.HyperBro, Win32/HyperBro, APT27.Payload · Sample count (EMBER 2018): 1 · Enrichment: insufficient_information · Updated: 2026-07-02T07:18:19Z

Category: TrojanActor: Unknown / CybercriminalIndustry: Global / OpportunisticMotivation: Opportunistic

Overview

Executive Summary

HyperBro is a custom, in-memory Remote Access Trojan (RAT) and backdoor exclusively utilized by the Chinese state-sponsored threat group APT27 (also known as Emissary Panda, Iron Tiger, or LuckyMouse). It is a highly sophisticated espionage tool designed to provide the attackers with long-term, stealthy, and unrestricted administrative access to compromised enterprise and government networks for the purpose of intellectual property theft and surveillance.

Infection Vector and Technical Capabilities

APT27 typically deploys HyperBro as a secondary payload after gaining initial access through the exploitation of public-facing server vulnerabilities (e.g., SharePoint, Exchange) or via targeted spear-phishing with malicious documents. Once deployed, HyperBro exhibits advanced APT capabilities:

In-Memory Execution (Fileless): HyperBro is designed to operate almost entirely in memory. It is often loaded using DLL side-loading techniques (hijacking legitimate, signed executables to load the malicious payload) or via reflective DLL injection, making it highly resistant to traditional on-disk antivirus scanning.
Custom C2 Protocols: It utilizes custom, encrypted communication protocols over HTTP/HTTPS to communicate with its Command and Control servers, often blending its traffic with legitimate network noise to evade perimeter detection.
Comprehensive Backdoor Capabilities: HyperBro grants the attacker total control. It can execute arbitrary shell commands, manage files (upload/download/delete), manipulate the Windows registry, log keystrokes, capture screenshots, and act as a proxy to pivot laterally deeper into the network.

Threat Assessment

A HyperBro detection is an absolute critical security incident (Code Red). It signifies an active, deep compromise by a highly resourced, Tier-1 state-sponsored adversary. The objective is stealthy, long-term espionage. If HyperBro is detected, it must be assumed that the attackers have already achieved broad lateral movement and likely possess Domain Admin credentials.

Incident Response and Remediation

Invoke Incident Response Retainer: A confirmed APT27 breach requires immediate escalation to specialized, external Incident Response (IR) teams and potentially national cyber security authorities.
Containment Strategy: Do not immediately remediate individual endpoints, as this will alert the adversary, causing them to "dig in" using alternative backdoors. Containment must be a coordinated, network-wide event to sever all access simultaneously.
Total Infrastructure Rebuild: Eradicating an APT requires fundamentally rebuilding compromised infrastructure, enforcing strict network segmentation, and implementing pervasive MFA, as the adversary likely possesses global administrative credentials.

Known aliases

Threat reports may refer to this family under multiple names:

MITRE ATT&CK Techniques

This family has been observed using the following ATT&CK techniques: T1574.002 T1055.001 T1071.001 T1056.001

Tactical Mitigations

Based on the techniques used by this family, consider the following defensive strategies:

T1056.001: Implement Endpoint Detection and Response (EDR) to monitor for suspicious API calls related to keystroke interception. Enforce Multi-Factor Authentication (MFA) to render stolen passwords useless.
T1071.001: Implement web filtering and SSL/TLS inspection to detect malicious command and control (C2) traffic hiding in HTTP/HTTPS.

Generated Detections (Boilerplate)

These YARA and Sigma rules are auto-generated based on the family name and aliases. They must be heavily tuned before deployment in a production environment.

YARA Rule

rule MALWARE_WIN_HYPERBRO {
    meta:
        description = "Detects Hyperbro (trojan)"
        author = "SystemHelpdesk Boilerplate Generator"
        date = "2026-07-06"
    strings:
        $s1 = "hyperbro" ascii wide nocase
        $s2 = "apt.hyperbro" ascii wide nocase
        $s3 = "backdoor.hyperbro" ascii wide nocase
        $s4 = "win32/hyperbro" ascii wide nocase
        $s5 = "apt27.payload" ascii wide nocase
    condition:
        uint16(0) == 0x5a4d and any of them
}

Sigma Rule

title: Suspicious Hyperbro Activity
id: c613c4eec069aa50feb6fd63756139cc
status: experimental
description: Detects generic indicators of the hyperbro malware family.
logsource:
    category: process_creation
    product: windows
detection:
    selection:
        Image|endswith:
            - '\cmd.exe'
            - '\powershell.exe'
        CommandLine|contains:
            - "*hyperbro*"
            - "*apt.hyperbro*"
            - "*backdoor.hyperbro*"
            - "*win32/hyperbro*"
            - "*apt27.payload*"
    condition: selection
level: medium

References & External Analysis

Search "hyperbro" on VirusTotal (External Analysis)

Frequently Asked Questions

How do I remove the Hyperbro Trojan from Windows?

Manual removal of Hyperbro is highly discouraged as it may leave persistence mechanisms intact. We recommend disconnecting the device from the internet and utilizing a professional incident response service or enterprise-grade EDR software to conduct a full forensic sweep.

Is Hyperbro a virus or a Trojan?

Hyperbro is classified as a Trojan. Unlike traditional viruses that infect files, modern malware like Hyperbro typically operates as a standalone payload designed to compromise systems, steal data, or deploy secondary stage implants.

What are the main symptoms of a Hyperbro infection?

Symptoms of Hyperbro can include unexpected system slowness, unauthorized outbound network traffic to unknown IP addresses, disabled security software, and suspicious background processes running from AppData or Temp directories.

Related Families (Category: trojan)

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Protect Your Network Against Trojans

Want to prevent Hyperbro and similar threats from compromising your organization? Read our comprehensive defensive guide: Banking Trojan Protection.

Need help with an active incident? Published by the SystemHelpdesk team.

Machine-readable

Get this profile as JSON: https://jordanricky1604-ship-it.github.io/malware-families-catalog/api/hyperbro.json

Ecosystem & Interactive Environments

This profile is part of the Malware Families Catalog, a public dataset of 2,899 malware families. The catalog is also published across our ecosystem: Hugging Face, Kaggle, Zenodo, Replit, StackBlitz, CodeSandbox, and CodePen.