GateKeeper
GateKeeper is an encrypted .NET payload associated with the financially motivated threat actor KongTuke, also tracked as Woodgnat. The available reporting describes it as a .NET payload with layered encryption, extensive anti-analysis logic, and victim-fingerprinting functionality. Huntress reported that in a January 2026 KongTuke campaign, GateKeeper appeared in the infection path used for non-domain-joined hosts after a ClickFix/CrashFix-style social-engineering chain involving a malicious NexShield browser extension, clipboard-staged PowerShell, and abuse of finger.exe as a LOLBin. In that reporting, the GateKeeper branch was part of a more obfuscated, DGA-driven chain that also used AMSI bypasses and was intended to withhold payloads from sandboxes; in analysis, one branch returned the string "TEST PAYLOAD!!!!," suggesting testing or staged rollout. GateKeeper has also been listed among other KongTuke tooling alongside WinPython, Node.js, finger.exe, the fake NexShield browser extension, MintsLoader, and D3F@ck Loader. High-confidence details in the provided content do not establish additional payload capabilities, persistence mechanisms, or specific indicators of compromise for GateKeeper beyond its role as an encrypted .NET payload with anti-analysis and fingerprinting behavior.
Hunt this family in your stack
Mallory pivots from this family to the IOCs, detections, and named campaigns that touch your stack, and pages you when something new lands.
Groups observed using it
2 distinct threat actors attributed by public researchers. Open in Mallory to see the full evidence chain and overlapping campaigns.
KongTuke has also been seen using a wider kit, including WinPython, Node.js, finger.exe, a fake NexShield browser extension, the encrypted GateKeeper .NET payload, and loaders like MintsLoader and D3F@ck Loader.
KongTuke has also been seen using a wider kit, including WinPython, Node.js, finger.exe, a fake NexShield browser extension, the encrypted GateKeeper .NET payload, and loaders like MintsLoader and D3F@ck Loader.
Techniques & procedures
4 distinct techniques documented for this family, organized by ATT&CK tactic.
Execution
2 techniques
Execution
In each case the victim is ultimately tricked into running an attacker-supplied PowerShell command... Once a command is executed, a multi-stage PowerShell chain downloads and unpacks a portable WinPython environment and launches the ModeloRAT Python scripts.
ClickFix... fake error or fake CAPTCHA tests to trick users into pasting malicious scripts into the Windows Run dialog... FileFix... manually pasting and executing malicious commands... CrashFix... trick them into manually executing code... In each case the victim is ultimately tricked into running an attacker-supplied PowerShell command.
Stealth
2 techniques
Stealth
Recent activity
10 sources tracked across advisories, community write-ups, and news. New activity surfaces here as Mallory finds it.
An encrypted .NET payload mentioned as part of the KongTuke/Woodgnat malware toolkit.
An encrypted .NET payload used by KongTuke as part of its toolset.
A .NET payload used in Woodgnat attack chains that employs layered encryption, anti-analysis measures, and victim fingerprinting.
A .NET payload used in Woodgnat attack chains that employs layered encryption, anti-analysis measures, and victim fingerprinting.
The version that knows your environment.
Match every observed IP, domain, and hash against your live telemetry.
Named campaigns wielding this family, with evidence pinned to each claim.
CVEs this family uses for access and lateral movement.
YARA, Sigma, Snort, and vendor rules, auto-deployed to your SIEM.
Every documented technique, ranked by evidence weight.
Reddit, Mastodon, and CTI community discussion around this family.