Nc.exe Windows

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Thegenuine nc.exe file is a software component of NetCat Network Control Program by Rodney Beede.

In 1995, someone called "hobbit" created NetCat for Unix and used the name "nc.exe"; Rodney Beede later adapted it to Windows NT (and later), where it needs the Minimalist GNU for Windows (MinGW) for an underlying Unix/Linux platform. It gives network administrators a "Swiss army knife" for testing TCP/IP connections and ports. It can usually be uninstalled by looking for "Network Control" under "Uninstall a Program" in the Control Panel. An early well-known MS-DOS freeware program called "Norton Commander" also existed for managing files. (A modern freeware version is called "winnc.exe".) Because these made "nc.exe" a popular name, it appears to be a popular imitation name for malware. NetCat's bare-metal TCP/IP port-level access is useful for testing a network but opens possibilities for abuse. The NetCat source code is free and widely shared so there are many potential versions and some trigger antivirus warnings, although these may be false.

The .exe extension on a filename indicates an executable file. Executable files may, in some cases, harm your computer. Therefore, please read below to decide for yourself whether the nc.exe on your computer is a Trojan that you should remove, or whether it is a file belonging to the Windows operating system or to a trusted application.

Important: Some malware also uses the file name nc.exe, for example HKTL_NETCAT (detected by TrendMicro), and not-a-virus:RemoteAdmin.Win32.NetCat.a (detected by Kaspersky). Therefore, you should check the nc.exe process on your PC to see if it is a threat. We recommend Security Task Manager for verifying your computer's security. This was one of the Top Download Picks of The Washington Post and PC World.

Summary: Average user rating of nc.exe: based on 33 votes with 19 user comments.9 users think nc.exe is essential for Windows or an installed application.6 users think it's probably harmless.4 users think it's neither essential nor dangerous.4 users suspect danger.10 users think nc.exe is dangerous and recommend removing it.2 users don't grade nc.exe ("not sure about it").

A clean and tidy computer is the key requirement for avoiding problems with nc. This means running a scan for malware, cleaning your hard drive using 1cleanmgr and 2sfc /scannow, 3uninstalling programs that you no longer need, checking for Autostart programs (using 4msconfig) and enabling Windows' 5Automatic Update. Always remember to perform periodic backups, or at least to set restore points.

Should you experience an actual problem, try to recall the last thing you did, or the last thing you installed before the problem appeared for the first time. Use the 6resmon command to identify the processes that are causing your problem. Even for serious problems, rather than reinstalling Windows, you are better off repairing of your installation or, for Windows 8 and later versions, executing the 7DISM.exe /Online /Cleanup-image /Restorehealth command. This allows you to repair the operating system without losing data.

To help you analyze the nc.exe process on your computer, the following programs have proven to be helpful: ASecurity Task Manager displays all running Windows tasks, including embedded hidden processes, such as keyboard and browser monitoring or Autostart entries. A unique security risk rating indicates the likelihood of the process being potential spyware, malware or a Trojan. BMalwarebytes Anti-Malware detects and removes sleeping spyware, adware, Trojans, keyloggers, malware and trackers from your hard drive.

No Metasploit! you told yourself, as you accepted the challenge of creating an exploit manually. Taking your time carefully preparing the exploit, will it work, will I get a shell? You run the exploit and are greeted with a reverse cmd.exe shell on the Windows victim, your excitement soon fades however as the post exploitation phase begins you need a way to transfer files. Fear not as there is a multitude of ways to transfer files to and from a Windows victim without advanced tools such as Metasploit.

The victim machine for this how-to is Jerry a machine from the Hack The Box pen-testing labs. Jerry is a fairly up to date Windows Server 2012 R2 machine. For the purpose of this how-to the machine is already exploited and a simple reverse shell is established from the victim to the attacker.

PowerShell, installed by default on most modern versions of Windows can be leveraged to download files over HTTP in several ways. Not all commands work on all Windows versions as some commands depend on newer versions of PowerShell and the available PowerShell modules on the victim.

The Background Intelligent Transfer Service, BITS for short and the built-in bitsadmin.exe command line utility can also be leveraged to download files over HTTP in the following way.

VBScript is a scripting language available on most versions of Windows and can also be leveraged to download files over HTTP. The following VBScript can be transferred to a victim by copy and pasting it between terminals on the attacker and victim machines.

Copy and pasting the code above will use the echo command to create a file on the victim with the name wget.vbs. This VBScript file can then be leveraged to download files over HTTP with the following command.

HTTP is a good way to get files from the attacking machine to the victim however there are other protocols and native utilities in Windows that can be leveraged to transfer files to and from the victim. SMB is such a protocol and is widely used within Windows environments. The protocol is usually blocked on edge firewalls so an initial foothold within the internal network is usually necessary to make use of SMB file transfers.

To simulate an SMB server on Kali the very popular ImPacket Python scripts from Core Security can be used. The ImPacket scripts are installed by default but a more recent version can usually be found at the aforementioned GitHub link.

Executing files over SMB is also possible, to demonstrate this nc.exe hosted on SHARE on the attacking machine can be leveraged to establish a reverse shell. An Ncat listener op port 4444 is prepared on the attacking machine to catch the connection.

Thus far Netcat has been used as an example file to be downloaded, uploaded and even executed over the network but Netcat itself can also be leveraged to transfer files between victim and attacker. For this to work Netcat has to be available on the victim machine.

To transfer a file from the victim to the attacker Ncat can be leveraged by piping input to a file. On the attacker an Ncat listener should be prepared that outputs incoming traffic to a file. To achieve this the > symbol can be used.

Most Windows versions old and new offer a command line FTP client by default. This FTP client can be leveraged to transfer files between victim and attacker. However, the ftp.exe utility on Windows is an interactive program. To prevent a non-interactive reverse shell from hanging indefinitely an FTP command file can be used.

Now that the FTP server is setup and running an FTP command file is needed on the victim. This command file can be leveraged in conjunction with the FTP client software to automatically login to the FTP server and download (GET) or upload (PUT) a file within a non-interactive reverse shell.

Thus far Jerry has been more than accommodating, however now it the time where using a fairly modern version of Windows is not an advantage as the TFTP command line utility is no longer installed by default on modern Windows versions.

It is possible however that an administrator installed it so it is certainly worth a mention, also the TFTP command line utility is still included by default on older versions of Windows such as Windows 2000 and Windows XP.

TFTP is a common protocol to make backups of configuration of network components such as switches and routers and is sometimes enabled within an internal network but is usually filtered at edge firewalls making it less likely to be used to over the internet.

Knowing how to transfer files manually using the default tools available on a victim increases your knowledge, flexibility and penetration testing skills, also knowing how to use the manual way has its charm.

I was however able to get into the failsafe by following the instruction in the wiki (pressing the QSS button after turning it on). I tried the instructions under the failsafe wiki aswell. I tried mount_root,firstboot and mtd -r erase rootfs_data. After issuing those commands and rebooting I still was not able to ssh or telnet to the router under normal conditions. I can only telnet under failsafe.

Is there a way for me to load a firmware on the router through the failsafe mode to revert to openwrt or even the stock firmware? I cant scp to the router and only my Windows 7 laptop seems to be able to connect to it under failsafe. Both my debian PC's cant connect.

First I put the router in failsafe mode again so I could access it. Then from windows I issued this command: nc -q0 192.168.1.1 1234

The firmware I wanted to put on the router being C:\firmware.bin

Netcat is a command line tool responsible for reading and writing data in the network. To exchange data, Netcat uses the network protocols TCP/IP and UDP. The tool originally comes from the world of Unix but is now available for all platforms.

Netcat can be used on all platforms via the command line. The command line tool is usually pre-installed on Linux and macOS. Windows users need to download the program from the internet. Special installation steps are not necessary; downloading the program file (nc.exe) is enough for use on Windows. You can then use Netcat with command prompt (cmd.exe) to carry out various network tasks. Start the command prompt as follows:

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