user@threatcheck.sh ~ threat-analysis
bash
$ analyze-threat PWS:MSIL/Browsstl.GG!MTB
PWS:MSIL/Browsstl.GG!MTB - Windows Defender threat signature analysis

PWS:MSIL/Browsstl.GG!MTB - Windows Defender Threat Analysis

$ cat analysis.txt
=== THREAT ANALYSIS REPORT ===
Threat Name: PWS:MSIL/Browsstl.GG!MTB
Classification:
Type:PWS
Platform:MSIL
Family:Browsstl
Detection Type:Concrete
Known malware family with identified signatures
Variant:GG
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: Password Stealer - Steals credentials and sensitive information for .NET (Microsoft Intermediate Language) platform, family Browsstl

Summary:

PWS:MSIL/Browsstl.GG!MTB is a concrete detection for a highly sophisticated browser credential stealer, targeting sensitive user data like cookies, credit cards, and login credentials from browsers such as Chromium and Firefox. It leverages extensive hooking, anti-analysis techniques, and various system utilities for persistence, execution, and data exfiltration.

Severity:
Critical
VDM Static Detection:
Relevant strings associated with this threat:
 - Debugger (PEHSTR_EXT)
 - !#HSTR:StringCodeForMshta.A!pli (PEHSTR_EXT)
 - !#HSTR:StringCodeForHooking.C!pli (PEHSTR_EXT)
 - !#HSTR:StringCodeForHooking.D!pli (PEHSTR_EXT)
 - !#HSTR:StringCodeForHooking.L!pli (PEHSTR_EXT)
 - !#HSTR:StringCodeForHooking.O!pli (PEHSTR_EXT)
 - !#HSTR:StringCodeForRegsvr32.A!pli (PEHSTR_EXT)
 - !#HSTR:StringCodeForRundll32.A!pli (PEHSTR_EXT)
 - rundll32 (PEHSTR_EXT)
 - !#HSTR:StringCodeForBITSJobs.A!pli (PEHSTR_EXT)
 - !#HSTR:StringCodeForPowerShell.G!pli (PEHSTR_EXT)
 - !#HSTR:StringCodeForScheduledTask.A!pli (PEHSTR_EXT)
 - !#HSTR:StringCodeForDataEncoding.D!pli (PEHSTR_EXT)
 - !#HSTR:StringCodeForHooking.J!pli (PEHSTR_EXT)
 - !#HSTR:StringCodeForHooking.K!pli (PEHSTR_EXT)
 - !#HSTR:StringCodeForRemoteFileCopy.B!pli (PEHSTR_EXT)
 - !#HSTR:ExecutionGuardrails (PEHSTR_EXT)
 - !#HSTR:StringCodeForFileDeletion.A!pli (PEHSTR_EXT)
 - !#HSTR:StringCodeForHooking.M!pli (PEHSTR_EXT)
 - !#HSTR:StringCodeForNetshHelperDLL.A!pli (PEHSTR_EXT)
 - !#HSTR:StringCodeForRemoteServices.A!pli (PEHSTR_EXT)
YARA Rule:
rule PWS_MSIL_Browsstl_GG_2147773589_0
{
    meta:
        author = "threatcheck.sh"
        detection_name = "PWS:MSIL/Browsstl.GG!MTB"
        threat_id = "2147773589"
        type = "PWS"
        platform = "MSIL: .NET intermediate language scripts"
        family = "Browsstl"
        severity = "Critical"
        info = "MTB: Microsoft Threat Behavior"
        signature_type = "SIGNATURE_TYPE_PEHSTR_EXT"
        threshold = "11"
        strings_accuracy = "High"
    strings:
        $x_1_1 = "Browsers" ascii //weight: 1
        $x_1_2 = "Chromium" ascii //weight: 1
        $x_1_3 = "Firefox" ascii //weight: 1
        $x_1_4 = "Cookies" ascii //weight: 1
        $x_1_5 = "Credentials" ascii //weight: 1
        $x_1_6 = "Credit_Cards" ascii //weight: 1
        $x_1_7 = "Credit_Cards_Data" ascii //weight: 1
        $x_1_8 = "Autofill" ascii //weight: 1
        $x_1_9 = "Sqlite" ascii //weight: 1
        $x_1_10 = "BCrypt" ascii //weight: 1
        $x_1_11 = "Debugger" ascii //weight: 1
        $x_1_12 = "get_IsAlive" ascii //weight: 1
    condition:
        (filesize < 20MB) and
        (11 of ($x*))
}
Known malware which is associated with this threat:
4dd7ebdae87ba28e49bbd828c1bb613c81c44d595be878532c2e8b7aac9c1414
06/01/2026
→VirusTotal↓Download Sample
Remediation Steps:
Immediately isolate affected systems, perform a full scan and removal of the malware using updated antivirus software. All potentially compromised credentials, especially those stored in web browsers, must be reset, and network activity should be closely monitored for exfiltration attempts.
=== END REPORT ===
$ reanalyze-threat
This analysis was last updated on 05/01/2026. Do you want to analyze it again?
$ ls available-commands/
→ cd /home
user@threatcheck.sh:~$ ▊