Krbanker

Overview

Trojan:Win32/Krbanker is a sophisticated financial trojan explicitly designed to target online banking customers, primarily focusing on financial institutions within South Korea. It aims to steal credentials, intercept two-factor authentication (2FA), and perform unauthorized fund transfers.

Understanding Krbanker
To the victim, Krbanker is entirely invisible until fraudulent transactions appear on their bank statements. For a security analyst, Krbanker represents a highly localized, targeted threat. Unlike global botnets (like Emotet), Krbanker's code, web injects, and C2 infrastructure are specifically tailored to bypass the unique security controls (such as AhnLab Safe Transaction or specific PKI certificate requirements) mandated by South Korean banks.

Execution and Financial Theft Tactics
Krbanker is typically distributed via spearphishing or by compromising regional websites to host exploit kits (`T1189`). Upon execution, it establishes persistence via Registry Run keys. It injects its core DLL into the web browser process (`T1055.001`). When the user navigates to a targeted Korean banking portal, Krbanker utilizes 'Man-in-the-Browser' (MitB) techniques (`T1185`). It injects malicious HTML directly into the DOM, creating fake pop-ups that request the user's security card numbers, account passwords, and digital certificates (`T1111`). It also frequently alters the DNS settings or the local `hosts` file (`T1562.002`) to redirect legitimate banking URLs to attacker-controlled phishing pages.

Indicators of Compromise & Impact
The primary impact is severe financial fraud. EDR platforms must alert on the injection of DLLs into browser processes or the unauthorized modification of the `C:\Windows\System32\drivers\etc\hosts` file. Network logs will reveal DNS resolution for legitimate banking domains pointing to anomalous, foreign IP addresses. Memory analysis is necessary to extract the specific web inject configurations.

MITRE ATT&CK Techniques

Observed techniques used by this family, mapped to the MITRE ATT&CK framework:

Tactical Mitigations

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

• T1185: Enforce strong MFA and use browser isolation or hardened browsers for sensitive financial or administrative portals to defeat session hijacking.

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_KRBANKER {
    meta:
        description = "Detects Krbanker (trojan)"
        author = "SystemHelpdesk Boilerplate Generator"
        date = "2026-07-06"
    strings:
        $s1 = "krbanker" ascii wide nocase
    condition:
        uint16(0) == 0x5a4d and any of them
}

Sigma Rule

title: Suspicious Krbanker Activity
id: 83943f0a7729c68015476dd5bbd9e53d
status: experimental
description: Detects generic indicators of the krbanker malware family.
logsource:
    category: process_creation
    product: windows
detection:
    selection:
        Image|endswith:
            - '\cmd.exe'
            - '\powershell.exe'
        CommandLine|contains:
            - "*krbanker*"
    condition: selection
level: medium

Containment & Response Steps

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

1. Instantly isolate the endpoint; the attacker has active, real-time control over the user's web browser sessions.
2. Initiate a mandatory password reset for all financial and corporate accounts accessed from the infected machine, utilizing a known-clean device.
3. Revoke and reissue any digital certificates (PKI) stored on the infected machine, as Krbanker specifically targets these for theft.
4. Audit the local `hosts` file and DNS settings to ensure traffic is not being actively redirected to phishing infrastructure.

What to Avoid

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

1. Do not allow the user to log into any sensitive portal to 'check their balance'; the MitB trojan will intercept the login and modify the displayed balance.
2. Avoid assuming a simple AV scan fixes the issue; banking trojans deeply hook into the OS and often require a full rebuild.

References & External Analysis

• Search "krbanker" on VirusTotal (External Analysis)

Frequently Asked Questions

Related Families (Category: trojan)

Explore other malware families in the same category:

• Pjzab0Jsupjb
• Gify
• Backswap
• Bolik
• Gamehuck

Machine-readable

Get this profile as JSON: https://jordan123234-malware-families-explorer.static.hf.space/api/krbanker.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.