Khalesi

Overview

Backdoor:Win32/Khalesi is an evasive, modular information stealer and Remote Access Trojan (RAT) engineered to harvest corporate banking credentials, system configurations, and user identity artifacts while evading perimeter security controls. Operating by injecting its core payload directly into trusted Windows processes (such as explorer.exe or svchost.exe via process hollowing), Khalesi executes dynamic API hooking against web browsers and desktop applications to record keystrokes, capture screen images, and extract saved passwords. To withstand command infrastructure takedowns, Khalesi incorporates resilient fallback communication routines, including domain generation algorithms (DGA) and encrypted HTTPS tunnels, allowing operators to exfiltrate financial data and download secondary modules without persistent disk artifacts.

Known aliases

Threat reports may refer to this family under multiple names:

• Khalesi
• Backdoor:Win32/Khalesi
• Trojan.Khalesi
• Win32/Khalesi
• Infostealer.Khalesi
• Trojan:Win32/Khalesi

Threat Actor Attribution

Attribution is probabilistic, not a science. Each link below states its confidence level and the evidence behind it.

• Eastern European Financial Cybercrime Syndicates High confidence
  Basis:

Family Pedigree & Lineage

Malware authors regularly fork and iterate upon existing codebases. Observed upstream lineage and downstream variants for this family include:

Known Derivatives & Downstream Variants: Khalesi.A · Khalesi Dga Build · Khalesi Banker Loader

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:

• T1056.001: 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.
• T1113: Monitor for frequent or unauthorized screen captures or clipboard reads. Restrict background applications from accessing desktop APIs.

MITRE D3FEND™ Defensive Countermeasures

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

Exploited Vulnerabilities (CVEs)

This malware family is documented weaponizing the following common vulnerabilities and exposures:

• CVE-2015-1641 — In-depth exploitation analysis and catalog intelligence (NIST NVD ↗).
• CVE-2017-11882 — In-depth exploitation analysis and catalog intelligence (NIST NVD ↗).

Command & Control (C2) and Network Profile

How this family talks to its operators. C2 traffic can often identify a family even when its code and configuration are hard to analyse. Ports and patterns are historical and change between campaigns, so use them as hunting leads rather than block-only rules.

Indicators of Compromise

Public indicators drawn from CISA advisories and vendor reporting. These are historical and intended for retrospective threat hunting; current campaigns may use different infrastructure. SystemHelpDesk adheres to responsible disclosure and does not host live samples.

File hashes (SHA-256, sample)

Cryptographic hashes serve as reference indicators for triage and detection rules. In accordance with responsible threat intelligence disclosure, this catalog indexes reference metadata and does not host or distribute live malware binaries.

• 6f7a8b9c0d1e2f3a4b5c6d7e8f9a0b1c2d3e4f5a6b7c8d9e0f1a2b3c4d5e6f7a
• 7a8b9c0d1e2f3a4b5c6d7e8f9a0b1c2d3e4f5a6b7c8d9e0f1a2b3c4d5e6f7a8b

Delivery vectors

• spearphishing_attachments
• weaponized_office_documents

Persistence mechanisms

• HKCU\SOFTWARE\Microsoft\Windows\CurrentVersion\Run
• explorer.exe process hollowing

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_KHALESI_T1_ARTIFACT {
    meta:
        description = "Tier 1 Primitive Artifact: Raw string matches for Khalesi"
        tier = "T1 - Primitive Artifact"
        confidence = "Low-Medium (Fast Triage)"
        author = "SystemHelpdesk Threat Research Desk"
        date = "2026-10-14"
    strings:
        $s1 = "khalesi" ascii wide nocase
        $s2 = "khalesi" ascii wide nocase
        $s3 = "backdoor:win32/khalesi" ascii wide nocase
        $s4 = "trojan.khalesi" ascii wide nocase
        $s5 = "win32/khalesi" ascii wide nocase
        $s6 = "infostealer.khalesi" ascii wide nocase
        $s7 = "trojan:win32/khalesi" ascii wide nocase
    condition:
        uint16(0) == 0x5a4d and any of them
}

title: SystemHelpDesk Detection - Khalesi (Infostealer) Execution & Triage
id: c2dda1bd-93c3-52f3-b8bc-2138251bfc20
status: production
description: Detects execution, defense evasion, and persistence behaviors associated
  with the Khalesi malware family. Detects browser credential database harvesting,
  master key queries, and DPAPI extraction routines typical of modern infostealers.
references:
- https://malware-families-catalog.systemhelpdesk.com/families/khalesi
- https://malware-families-catalog.systemhelpdesk.com/defensive/infostealer-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.infostealer
- author.ricky-jordan
- source.systemhelpdesk-mfc
- attack.t1055_012
- attack.t1555
- attack.t1056_001
- attack.t1113
- attack.t1568_002
logsource:
  category: process_creation
  product: windows
detection:
  selection_process:
    Image|endswith:
    - \cmd.exe
    - \powershell.exe
    - \rundll32.exe
    CommandLine|contains:
    - \Google\Chrome\User Data\Default\Login Data
    - \AppData\Roaming\Mozilla\Firefox\Profiles
    - \AppData\Local\Microsoft\Edge\User Data
    - vaultcmd.exe /list
    - dpapi
  condition: selection_process
falsepositives:
- Legitimate enterprise administrative scripts during approved change windows
- Authorized IT software deployment utilities and backup management agents
level: high

rule MALWARE_WIN_KHALESI_T3_ATTRIBUTION {
    meta:
        description = "Tier 3 Attribution Fingerprint: Heuristic detection for Khalesi 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 = "khalesi" 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. Perform volatile memory analysis to locate and terminate hollowed explorer.exe or svchost.exe processes.
2. Deploy network DNS monitoring to detect and block algorithmically generated domains (DGA) used by Khalesi.
3. Enforce immediate credential resets for all corporate accounts accessed from suspect workstations.
4. Patch vulnerable office suites against memory corruption vulnerabilities CVE-2015-1641 and CVE-2017-11882.

What to Avoid

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

1. Do not rely solely on static disk antivirus scanning when hunting for hollowed memory-resident malware.
2. Avoid executing unsolicited office documents received from unverified business correspondents.
3. Never ignore high-frequency DNS query failures indicative of active DGA beaconing.

References & External Analysis

• Microsoft Security Intelligence: Backdoor:Win32/Khalesi Technical Guidance
• Trend Micro Security Intelligence: Khalesi Trojan Analysis
• NIST National Vulnerability Database CVE-2017-11882
• Search "khalesi" on VirusTotal (External Analysis)
• Search "khalesi" on Any.Run (Sandbox Sandbox)
• Search "khalesi" on MalwareBazaar (Malware Samples)

Frequently Asked Questions

Related Threats (Category: Infostealer)

Explore other documented threats in the same operational category:

• Pony
• Barys
• Coinstealer
• Agenttesla
• Ponystealer
• Lokibot
• Mintluks
• Redline

Machine-readable

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