Ramnif
Table of Contents
Overview
Executive Summary
Ramnif is a heavily obfuscated alias and variant of the notorious **Ramnit** malware family. Originally discovered in 2010 as a self-replicating worm, Ramnit/Ramnif evolved into a highly sophisticated, modular Banking Trojan and botnet. It is designed for massive data theft, specifically targeting financial credentials, session cookies, and corporate FTP access.Propagation and Execution Lifecycle
Ramnif utilizes multiple vectors for distribution, including exploit kits (like Angler or RIG) hosted on compromised websites, malicious spam campaigns, and lateral movement via infected removable USB drives. Once a host is compromised, Ramnif's operations are extensive:- File Infection (Worm Capability): Unlike many modern trojans, Ramnif retains its original worm capabilities. It actively searches the local hard drive and attached network shares, injecting malicious code into `.exe`, `.dll`, and `.html` files. This file-infector capability makes complete eradication exceptionally difficult.
- Web Injection and Credential Theft: Ramnif acts as a classic banking trojan. It hooks into web browsers and utilizes Man-in-the-Browser (MitB) techniques to inject malicious HTML/JavaScript into legitimate banking websites. This allows it to steal login credentials, intercept two-factor authentication (2FA) codes, and alter transaction details in real-time.
- FTP Harvesting: The malware actively scans for and extracts stored credentials from popular FTP clients (like FileZilla or WinSCP), providing attackers with the keys to compromise external corporate web infrastructure.
Threat Assessment
A Ramnif infection is a severe, multi-faceted security incident. It represents an immediate financial threat due to banking credential theft, while its worm-like self-replication threatens to rapidly contaminate the entire corporate network, complicating incident response efforts.Eradication and Incident Response
- Aggressive Network Isolation: Due to its file-infecting nature, infected machines must be immediately disconnected from all internal networks and VPNs to halt the infection of shared network drives.
- Comprehensive System Re-image: Attempting to "clean" a Ramnif infection using antivirus software is highly risky because the malware alters legitimate system files. The only guaranteed method of eradication is a complete wipe and re-image of the compromised host from a known good baseline.
- Enterprise Password Reset: Following containment, all credentials utilized on the infected host—especially banking, VPN, and FTP passwords—must be immediately revoked and reset.
Known aliases
Threat reports may refer to this family under multiple names:
MITRE ATT&CK Techniques
Observed techniques used by this family, mapped to our technical analysis hubs and the official MITRE ATT&CK framework:
| Technique | Name | Tactic | Official Spec |
|---|---|---|---|
T1055 | Process Injection | Defense Evasion | ATT&CK ↗ |
T1056.004 | Input Capture: Credential API Hooking | Credential Access | ATT&CK ↗ |
T1114 | Email Collection (Harvesting addresses for spamming) | Collection | ATT&CK ↗ |
T1091 | Replication Through Removable Media (The core propagation mechanism using autorun.inf) | Lateral Movement | ATT&CK ↗ |
Tactical Mitigations
Based on the techniques used by this family, consider the following defensive strategies:
- T1056.004: Monitor for unauthorized keylogging, screen capturing, or web browser API hooking. Deploy EDR to detect API hooking.
MITRE D3FEND™ Defensive Countermeasures
Defensive techniques mapped to counter the offensive tradecraft observed in this family (via the MITRE D3FEND matrix):
| D3FEND ID | Countermeasure Name | Tactic | Countered ATT&CK | Defensive Guidance |
|---|---|---|---|---|
D3-PIAD | Process Injection Analysis & Detection | Detect | T1055 | Monitor cross-process thread creation (CreateRemoteThread) and asynchronous procedure calls (QueueUserAPC). |
D3-AHC | API Hook Detection | Detect | T1056.004 | Deploy kernel and userland EDR drivers to monitor SetWindowsHookEx and low-level keyboard hooks. |
D3-RMC | Removable Media Access Control | Harden | T1091 | Enforce Group Policy settings disabling Windows autorun and block execution permissions on removable USB storage media. |
D3-EAM | Email Access Monitoring | Detect | T1114 | Monitor Graph API and MAPI email harvesting routines and alert on bulk email downloads originating from unusual IP addresses. |
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:
Tier 1 Primitive Artifact Rule (Fast Triage)
Matches raw strings and file markers. Vulnerable to binary repacking and simple obfuscation.
rule MALWARE_WIN_RAMNIF_T1_ARTIFACT {
meta:
description = "Tier 1 Primitive Artifact: Raw string matches for Ramnif"
tier = "T1 - Primitive Artifact"
confidence = "Low-Medium (Fast Triage)"
author = "SystemHelpdesk Threat Research Desk"
date = "2026-10-14"
strings:
$s1 = "ramnif" ascii wide nocase
$s2 = "trojan.ramnit" ascii wide nocase
$s3 = "worm.ramnif" ascii wide nocase
$s4 = "win32/ramnit" ascii wide nocase
condition:
uint16(0) == 0x5a4d and any of them
}Tier 2 Behavioral Context Rule (Process Chains & Sigma)
Tracks parent-child process anomalies and suspicious scripting telemetry. Resilient against file renames.
title: SystemHelpDesk Detection - Ramnif (Trojan) Execution & Triage
id: 25c07dd3-f31c-5116-87ba-3a8d647f6f71
status: production
description: Detects execution, defense evasion, and persistence behaviors associated
with the Ramnif malware family. Detects suspicious execution from temporary user
directories with hidden window flags and background transfer utilities.
references:
- https://malware-families-catalog.systemhelpdesk.com/families/ramnif
- https://malware-families-catalog.systemhelpdesk.com/defensive/downloader-dropper-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.trojan
- author.ricky-jordan
- source.systemhelpdesk-mfc
- attack.t1055
- attack.t1056_004
- attack.t1114
- attack.t1091
logsource:
category: process_creation
product: windows
detection:
selection_process:
Image|endswith:
- \cmd.exe
- \powershell.exe
- \cscript.exe
- \wscript.exe
CommandLine|contains:
- AppData\Local\Temp
- -WindowStyle Hidden
- /e:jscript
- bitsadmin /transfer
condition: selection_process
falsepositives:
- Legitimate enterprise administrative scripts during approved change windows
- Authorized IT software deployment utilities and backup management agents
level: mediumTier 3 Attribution Fingerprint Rule (High Fidelity)
Deep signature matching distinctive operational fingerprints and payload characteristics.
rule MALWARE_WIN_RAMNIF_T3_ATTRIBUTION {
meta:
description = "Tier 3 Attribution Fingerprint: Heuristic detection for Ramnif 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 = "ramnif" 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.
- Sever network connectivity for the flagged endpoint to terminate persistent command-and-control (C2) communication channels and stop Ramnif from retrieving secondary stage payloads.
- Capture process memory triage to detect and terminate malicious threads injected by Ramnif into legitimate system processes such as explorer.exe or svchost.exe.
- Audit Windows Registry Run keys (HKCU\Software\Microsoft\Windows\CurrentVersion\Run) and Task Scheduler entries to locate and purge Ramnif persistence hooks.
- Deploy updated enterprise EDR detection signatures and conduct an out-of-band endpoint scan to isolate dropped binaries and staged payloads.
- Rotate all credentials, domain user passwords, and session cookies active on the system during the Ramnif execution timeframe.
What to Avoid
Common mistakes during response to this family that can destroy evidence, spread the infection, or worsen recovery.
- Do not assume the incident is resolved simply because an antivirus tool removed the initial Ramnif dropper; always verify that secondary payloads and persistence hooks have been eradicated.
- Avoid logging in with Domain Admin or privileged credentials on a machine suspected of running Ramnif until memory triage is complete.
- Do not delay host isolation; automated lateral movement and credential dumping can occur within minutes of initial execution.
References & External Analysis
- Search "ramnif" on VirusTotal (External Analysis)
- Search "ramnif" on Any.Run (Sandbox Sandbox)
- Search "ramnif" on MalwareBazaar (Malware Samples)
Frequently Asked Questions
What is Ramnif and what threat category does it belong to?
Ramnif is classified as a Trojan. Documented across security telemetry, it is engineered to execute unauthorized operations, establish persistent footholds on target endpoints, and facilitate malicious campaigns targeting enterprise and individual environments.
How does Ramnif establish persistence and evade defensive controls?
Ramnif typically establishes persistence through registry run keys, scheduled tasks, or service installations, while evading signature-based antivirus solutions through code obfuscation, memory injection, or anti-analysis sandbox checks.
What are the essential incident response steps for mitigating a Ramnif compromise?
Security teams responding to Ramnif should immediately isolate affected endpoints from the network, perform memory triage to capture volatile forensic artifacts, audit registry and startup persistence mechanisms, revoke exposed user credentials, and restore systems from verified, clean backups.
What secondary payloads and staging behaviors are commonly associated with Trojan.Ramnit?
Trojan.Ramnit frequently operates as a loader or dropper designed to establish a foothold before downloading and executing secondary high-impact malware payloads. Depending on the threat actor's objectives, these dropped modules can range from ransomware and banking injects to modular infostealers and remote management backdoors.
How can security operations teams effectively detect and hunt for Trojan.Ramnit across enterprise endpoints?
Defenders should hunt for Trojan.Ramnit by deploying behavioral endpoint detection and response (EDR) rules that monitor suspicious process spawning (such as cmd.exe or powershell.exe spawned from office documents or temporary directories), anomalous outbound network connections from non-browser binaries, and unauthorized modifications to Windows Run keys and scheduled task registries.
How do I remove the Ramnif Trojan from Windows?
Manual removal of Ramnif 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 Ramnif a virus or a Trojan?
Ramnif is classified as a Trojan. Unlike traditional viruses that infect files, modern malware like Ramnif typically operates as a standalone payload designed to compromise systems, steal data, or deploy secondary stage implants.
What are the main symptoms of a Ramnif infection?
Symptoms of Ramnif 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.
Protect Your Network Against Trojans
Want to prevent Ramnif and similar threats from compromising your organization? Read our comprehensive defensive guide: Banking Trojan Protection for Businesses.
📣 Threat Intel Correction or Update?
Notice an outdated IOC, unlisted alias, or disputed attribution? Threat researchers are invited to propose an update on GitHub or contact the SystemHelpDesk research desk. All community revisions are credited in our public CHANGELOG.
Machine-readable
Get this profile as JSON: https://malware-families-catalog.systemhelpdesk.com/api/ramnif.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.