feat: strict rules for netcat and sensitive files

Author: rahuldass19

src/qwed_new/guards/code_guard.py

@@ -73,8 +73,12 @@ def _verify_bash(self, code: str) -> Dict[str, Any]:
             (r"wget\s+.*\|\s*bash", "Pipe to Bash detected (RCE Risk)"),
             (r"rm\s+-rf", "Destructive command (rm -rf)"),
             (r":\(\)\{\s*:\|:\&\s*\}\;", "Fork Bomb detected"),
-            (r"nc\s+.*-e\s+/bin/sh", "Netcat Reverse Shell"),
+            (r"nc\s+", "Netcat usage detected (Data Exfiltration/Reverse Shell Risk)"),
+            (r"netcat\s+", "Netcat usage detected"),
             (r"/dev/tcp/", "Direct TCP connection (Reverse Shell Risk)"),
+            (r"/etc/passwd", "Sensitive file access (/etc/passwd)"),
+            (r"/etc/shadow", "Sensitive file access (/etc/shadow)"),
+            (r"id_rsa", "SSH Private Key access detected"),
             (r"base64\s+-d", "Base64 Decoding (Obfuscation Risk)"),
             (r"chmod\s+777", "Insecure permissions (chmod 777)"),
             (r"sudo\s+", "Privilege Escalation attempt (sudo)"),