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

Trojan:MSIL/Formbook.AMAJ!MTB - Windows Defender Threat Analysis

$ cat analysis.txt
=== THREAT ANALYSIS REPORT ===
Threat Name: Trojan:MSIL/Formbook.AMAJ!MTB
Classification:
Type:Trojan
Platform:MSIL
Family:Formbook
Detection Type:Concrete
Known malware family with identified signatures
Variant:AMAJ
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 Formbook

Summary:

This is a concrete detection of Trojan:MSIL/Formbook.AMAJ, a sophisticated information-stealing malware designed to exfiltrate sensitive data from compromised Windows systems. Its presence indicates a high-risk compromise with a low false positive risk, leveraging .NET intermediate language.

Severity:
Critical
VDM Static Detection:
No specific strings found for this threat
YARA Rule:
rule Trojan_MSIL_Formbook_AMAJ_2147915324_0
{
    meta:
        author = "threatcheck.sh"
        detection_name = "Trojan:MSIL/Formbook.AMAJ!MTB"
        threat_id = "2147915324"
        type = "Trojan"
        platform = "MSIL: .NET intermediate language scripts"
        family = "Formbook"
        severity = "Critical"
        info = "MTB: Microsoft Threat Behavior"
        signature_type = "SIGNATURE_TYPE_PEHSTR_EXT"
        threshold = "1"
        strings_accuracy = "Low"
    strings:
        $x_1_1 = {1f 16 5d 91 13 ?? 07 09 91 11 ?? 61 09 18 58 17 59 08 5d}  //weight: 1, accuracy: Low
    condition:
        (filesize < 20MB) and
        (all of ($x*))
}
Known malware which is associated with this threat:
Filename: HBL_TPA2610310_20260128103234076 - MV EVER MAGNA1440-003E.pdf.scr
d018cce8feede53d9464755079225cb6a52d8e277cbb0d49b4ec0fd984b4eb71
29/01/2026
→VirusTotal↓Download Sample
Filename: Alibaba Order list.exe
851eff1ee63fed8cc3c032689e157ae350dbf68a49a23192bad20277c409d477
29/01/2026
→VirusTotal↓Download Sample
Remediation Steps:
Immediately isolate the affected system to prevent further data exfiltration and network spread. Perform a full system scan with updated antivirus definitions, remove all detected malicious files, and investigate for any persistence mechanisms or additional compromise indicators. Reset all potentially exposed credentials and consider a system reimage due to the nature of info-stealing malware.
=== END REPORT ===
$ reanalyze-threat
This analysis was last updated on 29/01/2026. Do you want to analyze it again?
$ ls available-commands/
→ cd /home
user@threatcheck.sh:~$ ▊