user@threatcheck.sh ~ threat-analysis
bash
$ analyze-threat Backdoor:Linux/Gafgyt.BK!MTB
Backdoor:Linux/Gafgyt.BK!MTB - Windows Defender threat signature analysis

Backdoor:Linux/Gafgyt.BK!MTB - Windows Defender Threat Analysis

$ cat analysis.txt
=== THREAT ANALYSIS REPORT ===
Threat Name: Backdoor:Linux/Gafgyt.BK!MTB
Classification:
Type:Backdoor
Platform:Linux
Family:Gafgyt
Detection Type:Concrete
Known malware family with identified signatures
Variant:BK
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: Backdoor - Provides unauthorized remote access for Linux platform, family Gafgyt

Summary:

This detection identifies a backdoor from the Gafgyt family, a well-known botnet that targets Linux-based and IoT devices. Once infected, the system is controlled by an attacker and used to launch Distributed Denial of Service (DDoS) attacks and scan for other vulnerable devices to propagate.

Severity:
Medium
VDM Static Detection:
No specific strings found for this threat
YARA Rule:
rule Backdoor_Linux_Gafgyt_BK_2147818448_0
{
    meta:
        author = "threatcheck.sh"
        detection_name = "Backdoor:Linux/Gafgyt.BK!MTB"
        threat_id = "2147818448"
        type = "Backdoor"
        platform = "Linux: Linux platform"
        family = "Gafgyt"
        severity = "Critical"
        info = "MTB: Microsoft Threat Behavior"
        signature_type = "SIGNATURE_TYPE_ELFHSTR_EXT"
        threshold = "2"
        strings_accuracy = "High"
    strings:
        $x_2_1 = {8b 45 e0 c1 e0 02 03 45 e0 01 c0 89 45 e0 8b 45 0c 0f b6 00 0f b6 c0 03 45 e0 83 e8 30 89 45 e0 ff 45 0c 8b 45 0c 0f b6 00 3c 2f 76 0a 8b 45 0c 0f b6 00 3c 39}  //weight: 2, accuracy: High
    condition:
        (filesize < 20MB) and
        (all of ($x*))
}
Known malware which is associated with this threat:
Filename: SecuriteInfo.com.Linux.Siggen.1125.27863.11944
53332790a6261e07d6148b92f49a89208fdc0fd2faceffd9a8e5d21988c838b8
20/11/2025
→VirusTotal↓Download Sample
Remediation Steps:
Isolate the compromised Linux device from the network immediately. Remove the detected malicious file and analyze system logs to identify the initial access vector. Change all user and administrative passwords, apply all available security patches, and disable any unnecessary services like Telnet to prevent reinfection.
=== END REPORT ===
$ reanalyze-threat
This analysis was last updated on 20/11/2025. Do you want to analyze it again?
$ ls available-commands/
→ cd /home
user@threatcheck.sh:~$ ▊