user@threatcheck.sh ~ threat-analysis
bash
$ analyze-threat Trojan:MSIL/AsyncRat.ASY!MTB
Trojan:MSIL/AsyncRat.ASY!MTB - Windows Defender threat signature analysis

Trojan:MSIL/AsyncRat.ASY!MTB - Windows Defender Threat Analysis

$ cat analysis.txt
=== THREAT ANALYSIS REPORT ===
Threat Name: Trojan:MSIL/AsyncRat.ASY!MTB
Classification:
Type:Trojan
Platform:MSIL
Family:AsyncRat
Detection Type:Concrete
Known malware family with identified signatures
Variant:ASY
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: Trojan - Appears legitimate but performs malicious actions for .NET (Microsoft Intermediate Language) platform, family AsyncRat

Summary:

This detection identifies Trojan:MSIL/AsyncRat.ASY, a highly dangerous Remote Access Trojan (RAT) specifically targeting the .NET platform. AsyncRat allows attackers to gain full remote control over compromised systems, enabling surveillance, data exfiltration, and execution of arbitrary commands. The presence of specific PDB debugging paths in the detected file strongly confirms its identity as a malicious AsyncRat client.

Severity:
Critical
VDM Static Detection:
Relevant strings associated with this threat:
 - RAT\AsyncRat_0313\rat_Client\rat_pro\obj\Debug\rat_pro.pdb (PEHSTR_EXT)
 - loader\x64\Release\Espio.pdb (PEHSTR_EXT)
YARA Rule:
rule Trojan_MSIL_AsyncRat_ASY_2147848530_0
{
    meta:
        author = "threatcheck.sh"
        detection_name = "Trojan:MSIL/AsyncRat.ASY!MTB"
        threat_id = "2147848530"
        type = "Trojan"
        platform = "MSIL: .NET intermediate language scripts"
        family = "AsyncRat"
        severity = "Critical"
        info = "MTB: Microsoft Threat Behavior"
        signature_type = "SIGNATURE_TYPE_PEHSTR_EXT"
        threshold = "1"
        strings_accuracy = "Low"
    strings:
        $x_1_1 = {25 26 26 28 ?? ?? ?? 06 25 26 02 20 60 01 00 00 28 ?? ?? ?? 06 02 8e 69 28}  //weight: 1, accuracy: Low
    condition:
        (filesize < 20MB) and
        (all of ($x*))
}
Known malware which is associated with this threat:
Filename: FleetAgentEDR.exe
091867902dc7e6399ac313774512cff42bc097c4c20d5672e941fe50129af4a2
06/12/2025
→VirusTotal↓Download Sample
Filename: FleetAgentFUD.exe
072ce701ec0252eeddd6a0501555296bce512a7b90422addbb6d3619ae10f4ff
06/12/2025
→VirusTotal↓Download Sample
Remediation Steps:
Immediately isolate the affected system from the network to prevent further compromise or spread. Perform a full, deep scan with updated antivirus/EDR software to quarantine and remove all detected malicious files. Change all user and administrative credentials that may have been exposed, and conduct a thorough investigation to identify the initial infection vector.
=== END REPORT ===
$ reanalyze-threat
This analysis was last updated on 06/12/2025. Do you want to analyze it again?
$ ls available-commands/
→ cd /home
user@threatcheck.sh:~$ ▊