XWorm V5.6 Payload Fetching C2 Instructions From Pastebin


Zero‑Dwell Threat Intelligence Report

A narrative, executive‑ready view into the malware’s behavior, exposure, and reliable defenses.
Generated: 2025-11-27 12:57:26 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
knestcful.exe
Type
Win64 Executable (generic)
SHA‑1
de9ffe8dece95615367ee605ccf9c2ccf936d037
MD5
41a3d7a6ac2f2bb26877015c31419964
First Seen
2025-11-25 08:00:58.169233
Last Analysis
2025-11-25 09:02:44.359804
Dwell Time
0 days, 7 hours, 33 minutes

Extended Dwell Time Impact

For 1+ hours, this malware remained undetected — a limited but sufficient window for the adversary to complete initial execution and establish basic system access.

Comparative Context

Industry studies report a median dwell time closer to 21–24 days. This case represents rapid detection and containment within hours rather than days.

Timeline

Time (UTC) Event Elapsed
2025-11-24 20:10:07 UTC First VirusTotal submission
2025-11-27 06:50:27 UTC Latest analysis snapshot 2 days, 10 hours, 40 minutes
2025-11-27 12:57:26 UTC Report generation time 2 days, 16 hours, 47 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: 70. Detected as malicious: 57. Missed: 13. Coverage: 81.4%.

Detected Vendors

  • Xcitium
  • +56 additional vendors (names not provided)

List includes Xcitium plus an additional 56 vendors per the provided summary.

Missed Vendors

  • Acronis
  • Antiy-AVL
  • Baidu
  • CMC
  • MaxSecure
  • NANO-Antivirus
  • TACHYON
  • tehtris
  • VBA32
  • ViRobot
  • 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.

Behavioral Storyline — How the Malware Operates

This threat shows heavy registry manipulation (47.03% of total behavior), indicating persistent backdoor installation, configuration tampering, or system policy modification attempts. The malware likely establishes persistence mechanisms and modifies security settings to maintain long-term access.

Behavior Categories (weighted)

Weight values represent the frequency and intensity of malware interactions with specific system components. Higher weights indicate more aggressive targeting of that category. Each operation (registry access, file modification, network connection, etc.) contributes to the category’s total weight, providing a quantitative measure of the malware’s behavioral focus.

Category Weight Percentage
Registry 4407 47.03%
File System 2100 22.41%
System 1987 21.21%
Process 431 4.60%
Network 156 1.66%
Misc 111 1.18%
Device 58 0.62%
Crypto 44 0.47%
Threading 32 0.34%
Synchronization 26 0.28%
Hooking 5 0.05%
Com 5 0.05%
Windows 4 0.04%
Services 4 0.04%

MITRE ATT&CK Mapping

  • T1083 – get common file path
  • T1027 – encode data using XOR
  • T1222 – set file attributes
  • T1059 – accept command line arguments
  • T1546.001 – persist via default file association registry key
  • T1614 – get geographical location
  • T1083 – get file size
  • T1027 – encrypt data using RC4 PRGA
  • T1083 – check if file exists
  • T1129 – link function at runtime on Windows
  • T1082 – get disk information
  • T1129 – parse PE header

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
pastebin.com 172.66.171.73 United States Cloudflare, Inc.
www.aieov.com 76.223.54.146 United States Amazon.com, Inc.

Observed IPs

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

DNS Queries

Request Type
5isohu.com A
www.aieov.com A
pastebin.com A

Contacted IPs

IP Country ASN/Org
224.0.0.252
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 88 udp

UDP Packets

Source IP Dest IP Sport Dport Time Proto
192.168.56.14 192.168.56.255 137 137 3.102414131164551 udp
192.168.56.14 224.0.0.252 51209 5355 3.0215799808502197 udp
192.168.56.14 224.0.0.252 53401 5355 4.12353515625 udp
192.168.56.14 224.0.0.252 55094 5355 5.750133991241455 udp
192.168.56.14 224.0.0.252 55848 5355 3.021811008453369 udp
192.168.56.14 224.0.0.252 65148 5355 19.875344038009644 udp
192.168.56.14 8.8.4.4 49916 53 51.51535606384277 udp
192.168.56.14 8.8.4.4 50180 53 75.98433804512024 udp
192.168.56.14 8.8.4.4 50582 53 316.17172408103943 udp
192.168.56.14 8.8.4.4 50710 53 36.812268018722534 udp
192.168.56.14 8.8.4.4 50870 53 162.57859897613525 udp
192.168.56.14 8.8.4.4 50914 53 127.79730296134949 udp
192.168.56.14 8.8.4.4 51262 53 160.46882104873657 udp
192.168.56.14 8.8.4.4 51614 53 207.51545596122742 udp
192.168.56.14 8.8.4.4 52116 53 268.9529011249542 udp
192.168.56.14 8.8.4.4 52556 53 197.1720199584961 udp
192.168.56.14 8.8.4.4 52815 53 6.968860149383545 udp
192.168.56.14 8.8.4.4 53449 53 179.87470197677612 udp
192.168.56.14 8.8.4.4 53837 53 359.18774008750916 udp
192.168.56.14 8.8.4.4 54017 53 287.3592960834503 udp
192.168.56.14 8.8.4.4 54579 53 24.015871047973633 udp
192.168.56.14 8.8.4.4 54683 53 98.81244397163391 udp
192.168.56.14 8.8.4.4 55827 53 128.01561093330383 udp
192.168.56.14 8.8.4.4 55914 53 65.96902298927307 udp
192.168.56.14 8.8.4.4 56172 53 352.76589012145996 udp
192.168.56.14 8.8.4.4 56399 53 93.296865940094 udp
192.168.56.14 8.8.4.4 56716 53 266.281023979187 udp
192.168.56.14 8.8.4.4 56763 53 335.45356607437134 udp
192.168.56.14 8.8.4.4 56864 53 231.74984407424927 udp
192.168.56.14 8.8.4.4 57355 53 301.74987411499023 udp
192.168.56.14 8.8.4.4 57742 53 193.10979294776917 udp
192.168.56.14 8.8.4.4 59068 53 174.84394812583923 udp
192.168.56.14 8.8.4.4 59212 53 240.2028751373291 udp
192.168.56.14 8.8.4.4 60117 53 41.35947799682617 udp
192.168.56.14 8.8.4.4 60713 53 145.29670310020447 udp
192.168.56.14 8.8.4.4 61083 53 283.5465760231018 udp
192.168.56.14 8.8.4.4 61713 53 318.187283039093 udp
192.168.56.14 8.8.4.4 62022 53 80.45579504966736 udp
192.168.56.14 8.8.4.4 62055 53 300.89091515541077 udp
192.168.56.14 8.8.4.4 62112 53 22.406662940979004 udp
192.168.56.14 8.8.4.4 62548 53 113.2660620212555 udp
192.168.56.14 8.8.4.4 62800 53 146.0936930179596 udp
192.168.56.14 8.8.4.4 62997 53 254.57855796813965 udp
192.168.56.14 8.8.4.4 63205 53 110.62534308433533 udp
192.168.56.14 8.8.4.4 63906 53 344.7970390319824 udp
192.168.56.14 8.8.4.4 64452 53 214.4221169948578 udp
192.168.56.14 8.8.4.4 64753 53 58.70297908782959 udp
192.168.56.14 8.8.4.4 64950 53 330.421972990036 udp
192.168.56.14 8.8.4.4 65271 53 249.01569294929504 udp
192.168.56.14 8.8.4.4 65283 53 221.95324206352234 udp
192.168.56.14 8.8.8.8 49916 53 50.516247034072876 udp
192.168.56.14 8.8.8.8 50180 53 74.98509001731873 udp
192.168.56.14 8.8.8.8 50582 53 315.173583984375 udp
192.168.56.14 8.8.8.8 50710 53 35.822083950042725 udp
192.168.56.14 8.8.8.8 50870 53 161.5920021533966 udp
192.168.56.14 8.8.8.8 50914 53 126.79711294174194 udp
192.168.56.14 8.8.8.8 51262 53 159.4752790927887 udp
192.168.56.14 8.8.8.8 51614 53 206.52441000938416 udp
192.168.56.14 8.8.8.8 52116 53 267.96269512176514 udp
192.168.56.14 8.8.8.8 52556 53 196.17418909072876 udp
192.168.56.14 8.8.8.8 52815 53 7.968786954879761 udp
192.168.56.14 8.8.8.8 53449 53 178.8798451423645 udp
192.168.56.14 8.8.8.8 53837 53 358.2030861377716 udp
192.168.56.14 8.8.8.8 54017 53 286.36004400253296 udp
192.168.56.14 8.8.8.8 54579 53 23.015639066696167 udp
192.168.56.14 8.8.8.8 54683 53 97.81290602684021 udp
192.168.56.14 8.8.8.8 55827 53 127.02167105674744 udp
192.168.56.14 8.8.8.8 55914 53 64.96930193901062 udp
192.168.56.14 8.8.8.8 56172 53 351.7790460586548 udp
192.168.56.14 8.8.8.8 56399 53 92.29699516296387 udp
192.168.56.14 8.8.8.8 56716 53 265.29054498672485 udp
192.168.56.14 8.8.8.8 56763 53 334.46347403526306 udp
192.168.56.14 8.8.8.8 56864 53 230.7626130580902 udp
192.168.56.14 8.8.8.8 57355 53 300.75530910491943 udp
192.168.56.14 8.8.8.8 57742 53 192.11570715904236 udp
192.168.56.14 8.8.8.8 59068 53 173.85006093978882 udp
192.168.56.14 8.8.8.8 59212 53 239.2111189365387 udp
192.168.56.14 8.8.8.8 60117 53 40.35968208312988 udp
192.168.56.14 8.8.8.8 60713 53 144.31245613098145 udp
192.168.56.14 8.8.8.8 61083 53 282.5565810203552 udp
192.168.56.14 8.8.8.8 61713 53 317.1881239414215 udp
192.168.56.14 8.8.8.8 62022 53 79.45339298248291 udp
192.168.56.14 8.8.8.8 62055 53 299.90118503570557 udp
192.168.56.14 8.8.8.8 62112 53 21.40661907196045 udp
192.168.56.14 8.8.8.8 62548 53 112.26606702804565 udp
192.168.56.14 8.8.8.8 62800 53 145.10693907737732 udp
192.168.56.14 8.8.8.8 62997 53 253.5942211151123 udp
192.168.56.14 8.8.8.8 63205 53 109.62539505958557 udp
192.168.56.14 8.8.8.8 63906 53 343.80085802078247 udp
192.168.56.14 8.8.8.8 64452 53 213.4357089996338 udp
192.168.56.14 8.8.8.8 64753 53 57.703556060791016 udp
192.168.56.14 8.8.8.8 64950 53 329.4227740764618 udp
192.168.56.14 8.8.8.8 65271 53 248.01868605613708 udp
192.168.56.14 8.8.8.8 65283 53 220.9650411605835 udp

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

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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