Windows Directory Abused for Payload Placement by Nova Ransomware


Zero‑Dwell Threat Intelligence Report

A narrative, executive‑ready view into the malware’s behavior, exposure, and reliable defenses.
Generated: 2026-01-13 11:02:07 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
k7z0vonc8.exe
Type
Win64 Executable (generic)
SHA‑1
3f51c7cc580388f729dfa7f82b348d62a86da307
MD5
c66f1b118994d1884606d164a8631b83
First Seen
2026-01-12 12:38:34.625525
Last Analysis
2026-01-12 15:28:13.266679
Dwell Time
0 days, 7 hours, 33 minutes

Extended Dwell Time Impact

For 2+ 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
2025-11-06 16:46:30 UTC First VirusTotal submission
2026-01-13 09:30:01 UTC Latest analysis snapshot 67 days, 16 hours, 43 minutes
2026-01-13 11:02:07 UTC Report generation time 67 days, 18 hours, 15 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: 71. Detected as malicious: 45. Missed: 26. Coverage: 63.4%.

Detected Vendors

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

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

Missed Vendors

  • Acronis
  • Antiy-AVL
  • APEX
  • Avira
  • Baidu
  • ClamAV
  • CMC
  • CrowdStrike
  • Cynet
  • DrWeb
  • F-Secure
  • google_safebrowsing
  • Gridinsoft
  • huorong
  • Jiangmin
  • Sangfor
  • Skyhigh
  • SUPERAntiSpyware
  • TACHYON
  • tehtris
  • Trapmine
  • VirIT
  • 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

  • T1082 – get system information on Windows
  • T1027 – encode data using Base64
  • T1129 – link many functions at runtime
  • T1083 – get common file path
  • T1027 – encode data using XOR
  • T1129 – parse PE header
  • T1027 – encrypt data using RC4 PRGA
  • T1027 – encrypt data using speck
  • T1082 – query environment variable
  • T1129 – link function at runtime on Windows
  • T1083 – check if file exists

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
138 1 udp
5355 4 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 7.244515895843506 udp
192.168.56.13 192.168.56.255 138 138 13.245179891586304 udp
192.168.56.13 224.0.0.252 55150 5355 7.172592878341675 udp
192.168.56.13 224.0.0.252 60010 5355 9.728875875473022 udp
192.168.56.13 224.0.0.252 62406 5355 7.179720878601074 udp
192.168.56.13 224.0.0.252 63527 5355 9.190109968185425 udp
192.168.56.13 239.255.255.250 52252 3702 7.1857359409332275 udp
192.168.56.13 8.8.4.4 49311 53 10.870766878128052 udp
192.168.56.13 8.8.4.4 54881 53 11.746056079864502 udp
192.168.56.13 8.8.8.8 49311 53 11.869497060775757 udp
192.168.56.13 8.8.8.8 54881 53 12.744194030761719 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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