Win64 XWorm Backdoor Abuses Shell-Open Registry for Persistence


Zero‑Dwell Threat Intelligence Report

A narrative, executive‑ready view into the malware’s behavior, exposure, and reliable defenses.
Generated: 2025-11-27 12:51:50 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
key7f0.exe
Type
Win64 Executable (generic)
SHA‑1
57af71153fb4011d7a0f4c5b0f6db25554466341
MD5
6ae2c8579ade15a056bae300a0059bb1
First Seen
2025-11-25 08:01:53.990929
Last Analysis
2025-11-25 09:01:54.970057
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 19:28:25 UTC First VirusTotal submission
2025-11-27 07:01:34 UTC Latest analysis snapshot 2 days, 11 hours, 33 minutes
2025-11-27 12:51:50 UTC Report generation time 2 days, 17 hours, 23 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: 73. Detected as malicious: 63. Missed: 10. Coverage: 86.3%.

Detected Vendors

  • Xcitium
  • +62 additional vendors (names not provided)

List includes Xcitium plus an additional 62 vendors per the provided summary.

Missed Vendors

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

Dominant system-level operations (38.41% of behavior) suggest this malware performs deep system reconnaissance, privilege escalation, or core OS manipulation. It’s actively probing system defenses and attempting to gain administrative control.

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
System 883 38.41%
Registry 753 32.75%
File System 303 13.18%
Process 259 11.27%
Misc 58 2.52%
Synchronization 16 0.70%
Threading 15 0.65%
Device 6 0.26%
Hooking 4 0.17%
Windows 2 0.09%

MITRE ATT&CK Mapping

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

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 2.18.67.72 Europe Akamai Technologies
www.aieov.com 13.248.169.48 United States Amazon 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
www.msftncsi.com A
5isohu.com A
www.aieov.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 5 udp
53 14 udp
3702 1 udp

UDP Packets

Source IP Dest IP Sport Dport Time Proto
192.168.56.11 192.168.56.255 137 137 3.22664213180542 udp
192.168.56.11 192.168.56.255 138 138 9.333410024642944 udp
192.168.56.11 224.0.0.252 49563 5355 3.158155918121338 udp
192.168.56.11 224.0.0.252 54650 5355 3.1633810997009277 udp
192.168.56.11 224.0.0.252 55601 5355 3.496258020401001 udp
192.168.56.11 224.0.0.252 60205 5355 3.177889108657837 udp
192.168.56.11 224.0.0.252 62798 5355 5.724352121353149 udp
192.168.56.11 239.255.255.250 62184 3702 3.166985034942627 udp
192.168.56.11 8.8.4.4 51690 53 6.208164930343628 udp
192.168.56.11 8.8.4.4 51899 53 5.943604946136475 udp
192.168.56.11 8.8.4.4 56213 53 36.036335945129395 udp
192.168.56.11 8.8.4.4 58917 53 79.5205819606781 udp
192.168.56.11 8.8.4.4 59770 53 50.72350811958313 udp
192.168.56.11 8.8.4.4 62329 53 65.09877395629883 udp
192.168.56.11 8.8.4.4 63439 53 20.61534094810486 udp
192.168.56.11 8.8.8.8 51690 53 7.213180065155029 udp
192.168.56.11 8.8.8.8 51899 53 6.941924095153809 udp
192.168.56.11 8.8.8.8 56213 53 35.04033899307251 udp
192.168.56.11 8.8.8.8 58917 53 78.53408908843994 udp
192.168.56.11 8.8.8.8 59770 53 49.72434091567993 udp
192.168.56.11 8.8.8.8 62329 53 64.09919309616089 udp
192.168.56.11 8.8.8.8 63439 53 21.61405897140503 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

0

Registry Set

4

Services Started

0

Services Opened

0

Registry Opened (Top 25)

Show all (297 total)

Registry Set (Top 25)

Key Value
HKEY_USERS\S-1-5-21-575823232-3065301323-1442773979-1000\Software\Microsoft\SystemCertificates\Root\Certificates\0174E68C97DDF1E0EEEA415EA336A163D2B61AFD\Blob 5C 00 00 00 01 00 00 00 04 00 00 00 00 10 00 00 04 00 00 00 01 00 00 00 10 00 00 00 0D BE 92 DE FF 7D 36 BB 48 C4 A6 B1 15 24 95 38 0F 00 00 00 01 00 00 00 20 00 00 00 53 FE B9 19 2E D4 80 F2 09 12 4A 2C 57 D7 E8 97 7A 2E 9F 39 46 1D BF 21 4D F1 12 CB 16 02 4F A2 14 00 00 00 01 00 00 00 14 00 00 00 78 B8 30 FD 63 AC 7B 89 4A 07 3B ED F6 8A 83 9C C3 52 02 65 19 00 00 00 01 00 00 00 10 00 00 00 B5 74 AF 30 C5 C1 BA 3A 69 A7 10 02 00 82 4D D0 03 00 00 00 01 00 00 00 14 00 00 00 01 74 E6 8C 97 DD F1 E0 EE EA 41 5E A3 36 A1 63 D2 B6 1A FD 20 00 00 00 01 00 00 00 F8 05 00 00 30 82 05 F4 30 82 03 DC A0 03 02 01 02 02 09 00 E0 EA 61 4C 28 56 32 64 30 0D 06 09 2A 86 48 86 F7 0D 01 01 0B 05 00 30 81 8E 31 0B 30 09 06 03 55 04 06 13 02 49 4C 31 0F 30 0D 06 03 55 04 08 0C 06 43 65 6E 74 65 72 31 0C 30 0A 06 03 55 04 07 0C 03 4C 6F 64 31 10 30 0E 06 03 55 04 0A 0C 07 47 6F 50 72 6F 78 79 31 10 30 0E 06 03 55 04 0B 0C 07 47 6F 50 72 6F 78 79 31 1A 30 18 06 03 55 04 03 0C 11 67 6F 70 72 6F 78 79 2E 67 69 74 68 75 62 2E 69 6
HKEY_USERS\S-1-5-21-575823232-3065301323-1442773979-1000\Software\Microsoft\Windows\Windows Error Reporting\Debug\StoreLocation %LOCALAPPDATA%\Microsoft\Windows\WER\ReportArchive\AppCrash_audiodg.exe_2db737741eba1b98799813c3ce236094597e44a_0a9143c3
\\Registry\Machine\Software\Classes\exefile\shell\open\command\(Default)
\\Registry\Machine\Software\Classes\exefile\shell\open\command\IsolatedCommand

Services Started (Top 15)

Services Opened (Top 15)

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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