user@threatcheck.sh ~ threat-analysis
bash
$ analyze-threat VirTool:Win64/Myrddin.F!MTB
VirTool:Win64/Myrddin.F!MTB - Windows Defender threat signature analysis

VirTool:Win64/Myrddin.F!MTB - Windows Defender Threat Analysis

$ cat analysis.txt
=== THREAT ANALYSIS REPORT ===
Threat Name: VirTool:Win64/Myrddin.F!MTB
Classification:
Type:VirTool
Platform:Win64
Family:Myrddin
Detection Type:Concrete
Known malware family with identified signatures
Variant:F
Specific signature variant within the malware family
Suffix:!MTB
Detected via machine learning and behavioral analysis
Detection Method:Behavioral
Confidence:Very High
False-Positive Risk:Low

Concrete signature match: Virus Tool - Tool used to create or modify malware for 64-bit Windows platform, family Myrddin

Summary:

This is a concrete detection of VirTool:Win64/Myrddin.F, a malicious tool identified through machine learning behavioral analysis (!MTB) and specific string patterns. It exhibits capabilities related to network communication, potentially for command and control, managing client/server sessions, and may attempt to access or exfiltrate credentials.

Severity:
Critical
VDM Static Detection:
Relevant strings associated with this threat:
 - ).RemoteAddr (PEHSTR_EXT)
 - ).Hostname (PEHSTR_EXT)
 - ).Password (PEHSTR_EXT)
 - ).NewSession (PEHSTR_EXT)
 - ).Server (PEHSTR_EXT)
 - ).RemoteSock (PEHSTR_EXT)
 - AgentInfo (PEHSTR_EXT)
 - .ClientConn (PEHSTR_EXT)
 - |#d1e49aac-8f56-4280-b9ba-993a6d77406c (NID)
 - }#d1e49aac-8f56-4280-b9ba-993a6d77406c (NID)
 - |#75668c1f-73b5-4cf0-bb93-3ecf5cb7cc84 (NID)
 - }#75668c1f-73b5-4cf0-bb93-3ecf5cb7cc84 (NID)
 - &|#b2b3f03d-6a65-4f7b-a9c7-1c7ef74a9ba4 (NID)
 - &}#b2b3f03d-6a65-4f7b-a9c7-1c7ef74a9ba4 (NID)
 - |#5beb7efe-fd9a-4556-801d-275e5ffc04cc (NID)
 - }#5beb7efe-fd9a-4556-801d-275e5ffc04cc (NID)
 - |#01443614-cd74-433a-b99e-2ecdc07bfc25 (NID)
 - }#01443614-cd74-433a-b99e-2ecdc07bfc25 (NID)
 - |#7674ba52-37eb-4a4f-a9a1-f0f9a1619a2c (NID)
 - }#7674ba52-37eb-4a4f-a9a1-f0f9a1619a2c (NID)
 - |#92e97fa1-2edf-4476-bdd6-9dd0b4dddc7b (NID)
 - }#92e97fa1-2edf-4476-bdd6-9dd0b4dddc7b (NID)
 - |#c1db55ab-c21a-4637-bb3f-a12568109d35 (NID)
 - }#c1db55ab-c21a-4637-bb3f-a12568109d35 (NID)
 - |#e6db77e5-3df2-4cf1-b95a-636979351e5b (NID)
 - }#e6db77e5-3df2-4cf1-b95a-636979351e5b (NID)
 - |#d4f940ab-401b-4efc-aadc-ad5f3c50688a (NID)
 - }#d4f940ab-401b-4efc-aadc-ad5f3c50688a (NID)
YARA Rule:
rule VirTool_Win64_Myrddin_F_2147900127_0
{
    meta:
        author = "threatcheck.sh"
        detection_name = "VirTool:Win64/Myrddin.F!MTB"
        threat_id = "2147900127"
        type = "VirTool"
        platform = "Win64: Windows 64-bit platform"
        family = "Myrddin"
        severity = "Critical"
        info = "MTB: Microsoft Threat Behavior"
        signature_type = "SIGNATURE_TYPE_PEHSTR_EXT"
        threshold = "10"
        strings_accuracy = "High"
    strings:
        $x_1_1 = ").RemoteAddr" ascii //weight: 1
        $x_1_2 = ").Hostname" ascii //weight: 1
        $x_1_3 = ").Password" ascii //weight: 1
        $x_1_4 = "SetSessionTicket" ascii //weight: 1
        $x_1_5 = "addConn" ascii //weight: 1
        $x_1_6 = ").NewSession" ascii //weight: 1
        $x_1_7 = ").Server" ascii //weight: 1
        $x_1_8 = ").RemoteSock" ascii //weight: 1
        $x_1_9 = "AgentInfo" ascii //weight: 1
        $x_1_10 = ".ClientConn" ascii //weight: 1
    condition:
        (filesize < 20MB) and
        (all of ($x*))
}
Known malware which is associated with this threat:
Filename: SecuriteInfo.com.Win64.MerlinAgent-A.82525344
59a0e39ee85f0b91b458673811d6222a5cdd7ca36d6798ed9f3bc6f679478f92
25/12/2025
→VirusTotal↓Download Sample
Remediation Steps:
Immediately isolate the affected system, perform a full system scan with up-to-date antivirus/EDR, investigate for persistent mechanisms and C2 communication, and reset any potentially compromised user credentials. Ensure all systems are patched and security measures are enforced.
=== END REPORT ===
$ reanalyze-threat
This analysis was last updated on 25/12/2025. Do you want to analyze it again?
$ ls available-commands/
→ cd /home
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