Obfuscated Lynx Ransomware Dropper Executing Encrypted Secondary Payloads


Zero‑Dwell Threat Intelligence Report

A narrative, executive‑ready view into the malware’s behavior, exposure, and reliable defenses.
Generated: 2026-01-09 15:07:32 UTC

Executive Overview — What We’re Dealing With

This specimen has persisted long enough to matter. Human experts classified it as Malware, and the telemetry confirms a capable, evasive Trojan with real impact potential.

File
42a7cob.exe
Type
Win64 Executable (generic)
SHA‑1
1b7e1399da8205547dff07daff80f7d7375bdbb8
MD5
62536e936ef7929ae6db682899f4e8d5
First Seen
2026-01-08 13:01:27.868326
Last Analysis
2026-01-08 13:06:36.812508
Dwell Time
0 days, 7 hours, 33 minutes

Extended Dwell Time Impact

For 5+ minutes, this malware was rapidly detected — demonstrating excellent security controls that intercepted the threat during initial execution phases, severely limiting adversary capabilities.

Comparative Context

Industry studies report a median dwell time closer to 21–24 days. This case represents extremely rapid detection within minutes.

Timeline

Time (UTC) Event Elapsed
2025-12-04 21:12:35 UTC First VirusTotal submission
2026-01-09 14:18:08 UTC Latest analysis snapshot 35 days, 17 hours, 5 minutes
2026-01-09 15:07:32 UTC Report generation time 35 days, 17 hours, 54 minutes

Why It Matters

Every additional day of dwell time is not just an abstract number — it is attacker opportunity. Each day equates to more time for lateral movement, stealth persistence, and intelligence gathering.

Global Detection Posture — Who Caught It, Who Missed It

VirusTotal engines: 72. Detected as malicious: 45. Missed: 27. Coverage: 62.5%.

Detected Vendors

  • Xcitium
  • +44 additional vendors (names not provided)

List includes Xcitium plus an additional 44 vendors per the provided summary.

Missed Vendors

  • Acronis
  • ALYac
  • Antiy-AVL
  • Arcabit
  • Baidu
  • BitDefender
  • CAT-QuickHeal
  • CMC
  • Emsisoft
  • Fortinet
  • GData
  • google_safebrowsing
  • Gridinsoft
  • Jiangmin
  • MicroWorld-eScan
  • Panda
  • Sangfor
  • Skyhigh
  • SUPERAntiSpyware
  • TACHYON
  • tehtris
  • TrendMicro
  • VIPRE
  • Webroot
  • Yandex
  • ZoneAlarm
  • Zoner

Why it matters: if any endpoint relies solely on a missed engine, this malware can operate with zero alerts. Prevention‑first controls close that gap regardless of signature lag.

MITRE ATT&CK Mapping

  • T1140 – decode data using Base64 in .NET
  • T1027.002 – packed with Confuser
  • T1620 – load .NET assembly
  • T1129 – link function at runtime on Windows
  • T1562 – Tries to unhook or modify Windows functions monitored by CAPE
  • T1562.001 – Tries to unhook or modify Windows functions monitored by CAPE
  • T1027 – The binary likely contains encrypted or compressed data
  • T1027.002 – The binary likely contains encrypted or compressed data
  • T1539 – Touches a file containing cookies, possibly for information gathering
  • T1082 – Checks available memory
  • T1071 – Terminates another process
  • T1071 – Binary file triggered multiple YARA rules

Following the Trail — Network & DNS Activity

Outbound activity leans on reputable infrastructure (e.g., CDNs, cloud endpoints) to blend in. TLS sessions and
HTTP calls show routine beaconing and IP‑lookup behavior that can masquerade as normal browsing.

Contacted Domains

Domain IP Country ASN/Org
www.msftncsi.com 23.44.129.37 United States Akamai Technologies, Inc.

Observed IPs

IP Country ASN/Org
224.0.0.252
239.255.255.250
8.8.4.4 United States Google LLC
8.8.8.8 United States Google LLC

DNS Queries

Request Type
5isohu.com A
www.msftncsi.com A

Contacted IPs

IP Country ASN/Org
224.0.0.252
239.255.255.250
8.8.4.4 United States Google LLC
8.8.8.8 United States Google LLC

Port Distribution

Port Count Protocols
137 1 udp
5355 5 udp
53 4 udp
3702 1 udp

UDP Packets

Source IP Dest IP Sport Dport Time Proto
192.168.56.13 192.168.56.255 137 137 3.2462220191955566 udp
192.168.56.13 224.0.0.252 49311 5355 5.727304935455322 udp
192.168.56.13 224.0.0.252 55150 5355 3.171470880508423 udp
192.168.56.13 224.0.0.252 60010 5355 5.1815948486328125 udp
192.168.56.13 224.0.0.252 62406 5355 3.1767330169677734 udp
192.168.56.13 224.0.0.252 63527 5355 5.059773921966553 udp
192.168.56.13 239.255.255.250 52252 3702 3.180449962615967 udp
192.168.56.13 8.8.4.4 54879 53 7.7429468631744385 udp
192.168.56.13 8.8.4.4 54881 53 7.631304025650024 udp
192.168.56.13 8.8.8.8 54879 53 8.742352962493896 udp
192.168.56.13 8.8.8.8 54881 53 8.616991996765137 udp

Hunting tip: alert on unknown binaries initiating TLS to IP‑lookup services or unusual CDN endpoints — especially early in execution.

Persistence & Policy — Registry and Services

Registry and service telemetry points to policy awareness and environment reconnaissance rather than noisy persistence. Below is a compact view of the most relevant keys and handles; expand to see the full lists where available.

Registry Opened

101

Registry Set

0

Services Started

3

Services Opened

2

Registry Opened (Top 25)

Key
HKEY_LOCAL_MACHINE\SOFTWARE\WOW6432Node\Microsoft\.NETFramework\OnlyUseLatestCLR
HKEY_LOCAL_MACHINE\SOFTWARE\Classes\WOW6432Node\CLSID\{208D2C60-3AEA-1069-A2D7-08002B30309D}\ShellFolder\CallForAttributes
HKEY_LOCAL_MACHINE\SOFTWARE\Classes\WOW6432Node\CLSID\{95E15D0A-66E6-93D9-C53C-76E6219D3341}\AppID
HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Policies\Explorer\NoInternetIcon
HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Explorer
HKEY_CURRENT_USER\Software\Microsoft\.NETFramework
HKEY_LOCAL_MACHINE\Software\Microsoft\.NETFramework
HKEY_LOCAL_MACHINE\SOFTWARE\WOW6432Node\Microsoft\Windows\CurrentVersion\Explorer\Desktop\NameSpace\ValidateRegItems
HKEY_LOCAL_MACHINE\Software\Microsoft\Windows\CurrentVersion\Policies\NonEnum
HKEY_LOCAL_MACHINE\Software\Classes\CLSID\{208D2C60-3AEA-1069-A2D7-08002B30309D}\ShellFolder
HKEY_LOCAL_MACHINE\SOFTWARE\Classes\WOW6432Node\CLSID\{95E15D0A-66E6-93D9-C53C-76E6219D3341}\ActivateOnHostFlags
HKEY_LOCAL_MACHINE\SOFTWARE\WOW6432Node\Microsoft\.NETFramework\Fod
HKEY_LOCAL_MACHINE\SOFTWARE\Classes\WOW6432Node\CLSID\{208D2C60-3AEA-1069-A2D7-08002B30309D}\ShellFolder\FolderValueFlags
HKEY_CURRENT_USER\SOFTWARE\Microsoft\Windows\CurrentVersion\Explorer\SessionInfo\1
HKEY_LOCAL_MACHINE\SOFTWARE\WOW6432Node\Microsoft\.NETFramework\UseLegacyV2RuntimeActivationPolicyDefaultValue
HKEY_LOCAL_MACHINE\SOFTWARE\Classes\WOW6432Node\CLSID\{208D2C60-3AEA-1069-A2D7-08002B30309D}\ShellFolder\Attributes
HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Policies\Explorer\NoSetFolders
HKEY_LOCAL_MACHINE\SOFTWARE\Classes\WOW6432Node\CLSID\{871C5380-42A0-1069-A2EA-08002B30309D}\ShellFolder\FolderValueFlags
HKEY_LOCAL_MACHINE\SOFTWARE\Classes\WOW6432Node\CLSID\{871C5380-42A0-1069-A2EA-08002B30309D}\ShellFolder\Attributes
HKEY_LOCAL_MACHINE\SOFTWARE\Classes\WOW6432Node\CLSID\{871C5380-42A0-1069-A2EA-08002B30309D}\ShellFolder\RestrictedAttributes
HKEY_LOCAL_MACHINE\SOFTWARE\WOW6432Node\Microsoft\Windows\CurrentVersion\Explorer\Desktop\NameSpace\DelegateFolders\StorageDelegateSuppressionPolicy
HKEY_LOCAL_MACHINE\SOFTWARE\Classes\WOW6432Node\CLSID\{20D04FE0-3AEA-1069-A2D8-08002B30309D}\ShellFolder\FolderValueFlags
HKEY_LOCAL_MACHINE\Software\Microsoft\Windows\CurrentVersion\WindowsSystemLauncherTestHooks
HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Explorer\CLSID\{20D04FE0-3AEA-1069-A2D8-08002B30309D}\ShellFolder
HKEY_LOCAL_MACHINE\SOFTWARE\Classes\WOW6432Node\CLSID\{208D2C60-3AEA-1069-A2D7-08002B30309D}\ShellFolder\RestrictedAttributes
HKEY_LOCAL_MACHINE\SOFTWARE\Policies\Microsoft\Windows\CurrentVersion\Internet Settings\EnablePunycode
HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Explorer\Desktop\NameSpace\DelegateFolders
HKEY_LOCAL_MACHINE\Software\Microsoft\Windows\CurrentVersion\Internet Settings
HKEY_LOCAL_MACHINE\SOFTWARE\Classes\WOW6432Node\CLSID\{95E15D0A-66E6-93D9-C53C-76E6219D3341}\Elevation
HKEY_CURRENT_USER\SOFTWARE\Microsoft\Windows\CurrentVersion\Policies\Explorer\NoSetFolders
HKEY_LOCAL_MACHINE\Software\Microsoft\Windows\CurrentVersion\Explorer\CLSID\{20D04FE0-3AEA-1069-A2D8-08002B30309D}\ShellFolder
HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Explorer\CLSID\{871C5380-42A0-1069-A2EA-08002B30309D}\ShellFolder
HKEY_CURRENT_USER\Software\Classes\WOW6432Node\CLSID\{20D04FE0-3AEA-1069-A2D8-08002B30309D}\ShellFolder
HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Explorer\CLSID\{208D2C60-3AEA-1069-A2D7-08002B30309D}\ShellFolder
HKEY_CURRENT_USER\SOFTWARE\Policies\Microsoft\Windows\CurrentVersion\Internet Settings\CreateUriCacheSize
HKEY_LOCAL_MACHINE\SOFTWARE\Classes\WOW6432Node\CLSID\{20D04FE0-3AEA-1069-A2D8-08002B30309D}\ShellFolder\RestrictedAttributes
HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Policies\NonEnum\{20D04FE0-3AEA-1069-A2D8-08002B30309D}
HKEY_LOCAL_MACHINE\SOFTWARE\WOW6432Node\Microsoft\Windows\CurrentVersion\Explorer\Desktop\NameSpace\DelegateFolders\StorageDelegate
HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Policies\NonEnum\{208D2C60-3AEA-1069-A2D7-08002B30309D}
HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Internet Settings
HKEY_LOCAL_MACHINE\Software\Classes
HKEY_CURRENT_USER\Software\Classes
HKEY_LOCAL_MACHINE\SOFTWARE\Policies\Microsoft\Windows\CurrentVersion\Internet Settings\CreateUriCacheSize
HKEY_CURRENT_USER\Software\Classes\WOW6432Node\CLSID\{208D2C60-3AEA-1069-A2D7-08002B30309D}\ShellFolder
HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Explorer\Desktop\NameSpace
HKEY_LOCAL_MACHINE\Software\Policies\Microsoft\Windows\CurrentVersion\Internet Settings
HKEY_LOCAL_MACHINE\SOFTWARE\Policies\Microsoft\Windows\CurrentVersion\Internet Settings\Security_HKLM_only
HKEY_LOCAL_MACHINE\SOFTWARE\WOW6432Node\Microsoft\Windows\CurrentVersion\Explorer\Desktop\NameSpace\MonitorRegistry
HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Policies\Explorer\NoPropertiesMyComputer
HKEY_LOCAL_MACHINE\SOFTWARE\Classes\WOW6432Node\CLSID\{95E15D0A-66E6-93D9-C53C-76E6219D3341}\LocalServer32
Show all (101 total)
Key
HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Policies\Explorer
HKEY_LOCAL_MACHINE\SOFTWARE\WOW6432Node\Microsoft\Windows\CurrentVersion\Internet Settings\EnablePunycode
HKEY_CURRENT_USER\SOFTWARE\Microsoft\Windows\CurrentVersion\Policies\Explorer\NoCommonGroups
HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Policies\NonEnum
HKEY_LOCAL_MACHINE\SOFTWARE\Classes\WOW6432Node\CLSID\{95E15D0A-66E6-93D9-C53C-76E6219D3341}\InprocHandler32
HKEY_LOCAL_MACHINE\SOFTWARE\WOW6432Node\Microsoft\Windows\CurrentVersion\Explorer\Desktop\NameSpace\
HKEY_CURRENT_USER\SOFTWARE\Microsoft\Windows\CurrentVersion\Explorer\SessionInfo\1\Desktop\NameSpace\DelegateFolders
HKEY_LOCAL_MACHINE\SOFTWARE\WOW6432Node\Microsoft\Windows\CurrentVersion\Explorer\Desktop\NameSpace\DelegateFolders\
HKEY_LOCAL_MACHINE\Software\Classes\CLSID\{871C5380-42A0-1069-A2EA-08002B30309D}\ShellFolder
HKEY_LOCAL_MACHINE\SOFTWARE\Classes\WOW6432Node\CLSID\{95E15D0A-66E6-93D9-C53C-76E6219D3341}\InprocHandler
HKEY_CURRENT_USER\SOFTWARE\Policies\Microsoft\Windows\CurrentVersion\Internet Settings\EnablePunycode
HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\ShellCompatibility\Applications\executable.exe
HKEY_LOCAL_MACHINE\Software\Microsoft\Windows\CurrentVersion\Explorer\Desktop\NameSpace\DelegateFolders
HKEY_LOCAL_MACHINE\SOFTWARE\Classes\Interface\{4278CCC0-8710-543A-9036-F37DA6245536}
HKEY_CURRENT_USER\SOFTWARE\Microsoft\Windows\CurrentVersion\Policies\Explorer\NoPropertiesRecycleBin
HKEY_LOCAL_MACHINE\SOFTWARE\Classes\WOW6432Node\CLSID\{95E15D0A-66E6-93D9-C53C-76E6219D3341}\(Default)
HKEY_CURRENT_USER\Software\Classes\WOW6432Node\CLSID\{871C5380-42A0-1069-A2EA-08002B30309D}\ShellFolder
HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Policies\Explorer\NoPropertiesRecycleBin
HKEY_LOCAL_MACHINE\SOFTWARE\WOW6432Node\Microsoft\Windows\CurrentVersion\Internet Settings\CreateUriCacheSize
HKEY_CURRENT_USER\SOFTWARE\Microsoft\Windows\CurrentVersion\Explorer\Desktop\NameSpace\
HKEY_LOCAL_MACHINE\Software\Microsoft\.NETFramework\Advertised
HKEY_LOCAL_MACHINE\SOFTWARE\WOW6432Node\Microsoft\.NETFramework\InstallRoot
HKEY_CURRENT_USER\SOFTWARE\Microsoft\Windows\CurrentVersion\Internet Settings\EnablePunycode
HKEY_CURRENT_USER\SOFTWARE\Microsoft\Windows\CurrentVersion\Policies\Explorer\NoControlPanel
HKEY_LOCAL_MACHINE\SOFTWARE\Classes\WOW6432Node\CLSID\{95E15D0A-66E6-93D9-C53C-76E6219D3341}\LocalServer
HKEY_CURRENT_USER\SOFTWARE\Microsoft\Windows\CurrentVersion\Explorer\CLSID\{871C5380-42A0-1069-A2EA-08002B30309D}\ShellFolder\Attributes
HKEY_LOCAL_MACHINE\SOFTWARE\Classes\WOW6432Node\CLSID\{20D04FE0-3AEA-1069-A2D8-08002B30309D}\ShellFolder\CallForAttributes
HKEY_CURRENT_USER\SOFTWARE\Microsoft\Windows\CurrentVersion\Policies\Explorer\NoPropertiesMyComputer
HKEY_CURRENT_USER\Software\Classes\CLSID\{871C5380-42A0-1069-A2EA-08002B30309D}\ShellFolder
HKEY_LOCAL_MACHINE\SOFTWARE\Classes\WOW6432Node\Interface\{4278CCC0-8710-543A-9036-F37DA6245536}\ProxyStubClsid32
HKEY_CURRENT_USER\SOFTWARE\Microsoft\Windows\CurrentVersion\Policies\Explorer\NoInternetIcon
HKEY_LOCAL_MACHINE\SYSTEM\ControlSet001\Services\LanmanWorkstation\Parameters\RpcCacheTimeout
HKEY_LOCAL_MACHINE\SOFTWARE\Classes\WOW6432Node\CLSID\{20D04FE0-3AEA-1069-A2D8-08002B30309D}\ShellFolder\Attributes
HKEY_LOCAL_MACHINE\SOFTWARE\Classes\DelegateFolders
HKEY_CURRENT_USER\SOFTWARE\Microsoft\Windows\CurrentVersion\Internet Settings\CreateUriCacheSize
HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Policies\NonEnum\{871C5380-42A0-1069-A2EA-08002B30309D}
HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Policies\Explorer\NoCommonGroups
HKEY_LOCAL_MACHINE\Software\Microsoft\Windows\CurrentVersion\Explorer\CLSID\{208D2C60-3AEA-1069-A2D7-08002B30309D}\ShellFolder
HKEY_CURRENT_USER\Software\Policies\Microsoft\Windows\CurrentVersion\Internet Settings
HKEY_LOCAL_MACHINE\SOFTWARE\WOW6432Node\Microsoft\.NETFramework\ErrorDialog
HKEY_CURRENT_USER\SOFTWARE\Microsoft\Windows\CurrentVersion\Explorer\SessionInfo\1\Desktop\NameSpace
HKEY_CURRENT_USER\Software\Classes\CLSID\{208D2C60-3AEA-1069-A2D7-08002B30309D}\ShellFolder
HKEY_LOCAL_MACHINE\SOFTWARE\Classes\WOW6432Node\CLSID\{871C5380-42A0-1069-A2EA-08002B30309D}\ShellFolder\CallForAttributes
HKEY_LOCAL_MACHINE\Software\Microsoft\Windows\CurrentVersion\Policies\Explorer
HKEY_LOCAL_MACHINE\SOFTWARE\Classes\CLSID\{95E15D0A-66E6-93D9-C53C-76E6219D3341}
HKEY_LOCAL_MACHINE\SOFTWARE\Classes\WOW6432Node\Interface\{4278CCC0-8710-543A-9036-F37DA6245536}\ProxyStubClsid32\(Default)
HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Policies\Explorer\NoControlPanel
HKEY_LOCAL_MACHINE\Software\Classes\CLSID\{20D04FE0-3AEA-1069-A2D8-08002B30309D}\ShellFolder
HKEY_LOCAL_MACHINE\SOFTWARE\Classes\WOW6432Node\CLSID\{95E15D0A-66E6-93D9-C53C-76E6219D3341}\TreatAs
HKEY_CURRENT_USER\Software\Classes\CLSID\{20D04FE0-3AEA-1069-A2D8-08002B30309D}\ShellFolder
HKEY_LOCAL_MACHINE\Software\Microsoft\Windows\CurrentVersion\Explorer\Desktop\NameSpace

Registry Set (Top 25)

Services Started (Top 15)

Service
WSearch
lfsvc
BITS

Services Opened (Top 15)

Service
VaultSvc
clipsvc

What To Do Now — Practical Defense Playbook

  • Contain unknowns: block first‑run binaries by default — signatures catch up, containment works now.
  • EDR controls: alert on keyboard hooks, screen capture APIs, VM/sandbox checks, and command‑shell launches.
  • Registry watch: flag queries/sets under policy paths (e.g., …\FipsAlgorithmPolicy\*).
  • Network rules: inspect outbound TLS to IP‑lookup services and unexpected CDN endpoints.
  • Hunt broadly: sweep endpoints for the indicators above and quarantine positives immediately.

Dwell time equals attacker opportunity. Reducing execution privileges and egress shrinks that window even when vendors disagree.

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