Tongji

Overview

Executive Summary

Distribution and Technical Behavior

• Aggressive Telemetry: Tongji continuously tracks the user's browsing history, search queries, application usage, and sometimes keystrokes. This data is aggregated and transmitted to remote analytics servers in plaintext or using weak encryption.
• Traffic Interception: The software frequently installs a local proxy server or malicious browser extensions to intercept web traffic, overlaying legitimate websites with intrusive pop-ups, pop-unders, and sponsored content.
• Browser Hijacking: It forcibly alters the default search engine, homepage, and new tab settings to redirect all traffic through affiliate-linked portals controlled by the adware operators.

Risk Assessment

Mitigation and Removal Strategies

• Endpoint Scanning: Utilize a reputable enterprise-grade anti-malware solution to perform a deep system scan, targeting the Tongji executables, hidden scheduled tasks, and persistent registry keys used for tracking.
• Browser Remediation: Manually inspect and remove any unknown or unauthorized extensions from all installed web browsers. Perform a complete factory reset of the browsers to clear hijacked proxy and search settings.
• Application Control: Enforce strict application whitelisting policies to prevent standard users from executing unapproved software installers that frequently bundle this type of spyware.

Known aliases

Threat reports may refer to this family under multiple names:

• Adware.Tongji
• Spyware.Tongji
• PUP.Tongji

MITRE ATT&CK Techniques

Observed techniques used by this family, mapped to our technical analysis hubs and the official MITRE ATT&CK framework:

Tactical Mitigations

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

• T1056: Monitor for unauthorized keylogging, screen capturing, or web browser API hooking. Deploy EDR to detect API hooking.
• T1566.002: Inspect email links for known malicious domains and use link-rewriting services for time-of-click analysis.

MITRE D3FEND™ Defensive Countermeasures

Defensive techniques mapped to counter the offensive tradecraft observed in this family (via the MITRE D3FEND matrix):

Tiered Detection Rules (Cisco CAIRN Model)

Modern threat detection requires multi-layered rule engineering. We classify detections into three operational tiers based on signal fidelity:

rule MALWARE_WIN_TONGJI_T1_ARTIFACT {
    meta:
        description = "Tier 1 Primitive Artifact: Raw string matches for Tongji"
        tier = "T1 - Primitive Artifact"
        confidence = "Low-Medium (Fast Triage)"
        author = "SystemHelpdesk Threat Research Desk"
        date = "2026-10-14"
    strings:
        $s1 = "tongji" ascii wide nocase
        $s2 = "adware.tongji" ascii wide nocase
        $s3 = "spyware.tongji" ascii wide nocase
        $s4 = "pup.tongji" ascii wide nocase
    condition:
        uint16(0) == 0x5a4d and any of them
}

title: SystemHelpDesk Detection - Tongji (Ransomware) Execution & Triage
id: f1c84407-2ff8-58f8-9764-0e9a03b4e892
status: production
description: Detects execution, defense evasion, and persistence behaviors associated
  with the Tongji malware family. Detects volume shadow copy deletion, boot status
  tampering, and recovery inhibition characteristic of modern ransomware operations.
references:
- https://malware-families-catalog.systemhelpdesk.com/families/tongji
- https://malware-families-catalog.systemhelpdesk.com/defensive/ransomware-protection
- https://malware-families-catalog.systemhelpdesk.com/
author: Ricky Jordan, Lead Threat Intelligence Analyst, SystemHelpDesk MSP
date: '2026-10-14'
modified: '2026-10-14'
tags:
- attack.ransomware
- author.ricky-jordan
- source.systemhelpdesk-mfc
- attack.t1566_002
- attack.t1176
- attack.t1112
- attack.t1056
logsource:
  category: process_creation
  product: windows
detection:
  selection_process:
    Image|endswith:
    - \vssadmin.exe
    - \wmic.exe
    - \wbadmin.exe
    - \bcdedit.exe
    CommandLine|contains:
    - delete shadows
    - shadowcopy delete
    - resize shadowstorage
    - recoveryenabled no
    - ignoreallfailures
  condition: selection_process
falsepositives:
- Legitimate enterprise administrative scripts during approved change windows
- Authorized IT software deployment utilities and backup management agents
level: critical

rule MALWARE_WIN_TONGJI_T3_ATTRIBUTION {
    meta:
        description = "Tier 3 Attribution Fingerprint: Heuristic detection for Tongji tradecraft"
        tier = "T3 - Attribution Fingerprint"
        confidence = "High (Confirmed Family Signature)"
        author = "SystemHelpdesk Threat Research Desk"
        date = "2026-10-14"
    strings:
        // Core family identifier & heuristic payload signatures
        $attrib_str = "tongji" ascii wide nocase
        $pe_magic = "MZ" ascii
        $net_marker = "http" ascii nocase
    condition:
        uint16(0) == 0x5a4d and ($attrib_str and $net_marker) and filesize < 15MB
}

Containment & Response Steps

Ordered checklist for responders. Adapt to your environment and engage professional support for active incidents.

1. Immediately isolate affected host(s) from the internal network (disconnect physical Ethernet and disable Wi-Fi/Bluetooth) to prevent Tongji from spreading laterally or encrypting network-attached storage (NAS) and shared SMB volumes.
2. Preserve volatile system memory (RAM capture) on a representative endpoint before attempting a reboot or power-down, as Tongji symmetric encryption keys or uncompiled payload components may still reside in memory.
3. Audit process execution logs and terminate active scripting interpreters (e.g. PowerShell, CMD, WScript) or commands executing 'vssadmin.exe delete shadows' or 'wbadmin' used by Tongji to inhibit recovery.
4. Investigate the initial compromise vector (such as exposed RDP instances, spearphishing attachments, or vulnerable edge gateways) and enforce an immediate credential reset for all compromised Active Directory accounts.
5. Restore critical assets and databases exclusively from verified, air-gapped, or immutable offline backups once the Tongji binary and related persistence hooks are eradicated.

What to Avoid

Common mistakes during response to this family that can destroy evidence, spread the infection, or worsen recovery.

1. Do not restart or power cycle infected systems prematurely; doing so destroys volatile RAM encryption keys and may trigger bootloader locking logic embedded in Tongji.
2. Avoid negotiating or paying the extortion demand without prior forensic evaluation and consultation with incident response specialists, as payment does not guarantee data recovery.
3. Do not connect clean backup drives or external storage to the affected network until Tongji eradication is completely verified.

References & External Analysis

• Search "tongji" on VirusTotal (External Analysis)
• Search "tongji" on Any.Run (Sandbox Sandbox)
• Search "tongji" on MalwareBazaar (Malware Samples)

Frequently Asked Questions

Related Threats (Category: Ransomware)

Explore other documented threats in the same operational category:

• Irplan
• Genericgb
• W10Tweak
• Mazben
• Xiquitir
• Mediaget
• Hiddentears
• Satan

Machine-readable

Get this profile as JSON: https://malware-families-catalog.systemhelpdesk.com/api/tongji.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.