MoustachedBouncer
MoustachedBouncer is a cyberespionage group active since at least 2014 that targets foreign embassies in Belarus. The content describes it as a sophisticated Belarus-aligned group and states that since 2020 it has most likely been able to perform adversary-in-the-middle attacks at the ISP level. The group uses two separate toolsets named NightClub and Disco. A low-confidence link to Winter Vivern is mentioned, and tactical overlap with tools used in campaigns linked to Turla is also noted. Observed tradecraft in the provided content includes content injection into DNS, HTTP, and SMB replies to redirect selected victims to a fake Windows Update page that delivered malware; use of JavaScript delivered through HTML pages to deliver malware; plugins to execute PowerShell scripts; plugins to take screenshots; and plugins to save captured screenshots to the .\AActdata\ directory on an SMB share. The group also used a reverse proxy tool similar to revsocks, exploited CVE-2021-1732 to execute malware components with elevated rights, packed malware plugins with Themida, and used legitimate-looking filenames for malicious executables, including MicrosoftUpdate845255.exe. ATT&CK techniques explicitly associated in the content include T1059.001 (PowerShell), T1059.007 (JavaScript), T1659 (Content Injection), T1074.002 (Remote Data Staging), T1068 (Exploitation for Privilege Escalation), T1027.002 (Software Packing), T1090 (Proxy), T1113 (Screen Capture), and T1655.001 (Match Legitimate Name or Location). Known aliases in the content are moustachedbouncer and moushtachedbouncer.
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Tradecraft
37 distinct techniques observed across reporting, grouped by tactic. Hover any cell for the evidence excerpt; click through for MITRE's full description.
Associated malware families
7 malware families attributed to this actor across reporting.
2 additional families tracked in Mallory.
Associated vulnerabilities
2 CVEs this actor has used in observed campaigns. 2 of them exploited in the wild.
Executes C:\Users\Public\driverpack\driverpackUpdate.exe (the plugin above) using elevated rights via CVE-2021-1732.
This detection identifies instances where Windows Explorer.exe spawns PowerShell or cmd.exe processes, particularly focusing on executions initiated by LNK files. This behavior is associated with the ZDI-CAN-25373 Windows shortcut zero-day vulnerability, where specially crafted LNK files are used to trigger malicious code execution through cmd.exe or powershell.exe. This technique has been actively exploited by multiple APT groups in targeted attacks through both HTTP and SMB delivery methods.
Observables
4 indicators attributed to this actor: domains, IPs, hashes, and other artifacts pulled from reporting. View more in app.
Recent activity
20 sources tracked across advisories, community write-ups, and news. New activity surfaces here as Mallory finds it.
Listed in the detection annotations as a threat actor associated with exploitation for privilege escalation.
Listed as a threat actor associated with the PowerShell P/Invoke process injection API chain detection and related ATT&CK techniques.
Listed as a threat actor associated with PowerShell execution behavior relevant to this detection analytic.
Listed as a threat actor associated with use of Cobalt Strike PowerShell loader patterns.
The version that knows your environment.
Match sector + geo + tech-stack targeting against your real footprint.
Every observed MITRE ATT&CK technique, grouped by tactic.
Families this actor is known to deploy, with IOCs and behavior.
CVEs this actor has used in known campaigns.
YARA, Sigma, Snort, and vendor rules, auto-deployed to your SIEM.
Domains, IPs, and hashes tied to this actor, refreshed continuously.