Millions of apps and software are downloaded onto mobiles and PCs on a daily basis. But have we ever checked if it is safe or not? Malware is one of the top concerns for cybersecurity enthusiasts today, and that is what makes software developers ensure that their software is digitally signed. Now, you must be wondering what a digital signature is, how to sign exe, and what is an exe file. Well, let’s read ahead and find out!
If you have witnessed an unknown publisher security warning on your PC while installing software, it is probably because of an untrusted certificate. This can be a lame way for hackers or cybercriminals to get into your system, but as long as your PC has Windows Defender, you are safe.
The defender ensures that if the software or an executable file is not digitally signed by an authorized entity, it will not be installed on the system.
Now, let’s answer the question, how to sign an exe file? The process to sign an executable software file is super easy, provided you have the code signing certificate and the .exe file.
How to Sign an Executable File?
Let’s say that the name of your software file is ABCsoftware.exe. Here are the steps to sign an executable file!
- Open the command prompt window by typing in cmd in the search at the bottom of your PC screen. If using any Windows version below 10, tap the Windows icon on the keyboard and type cmd.
- On the command prompt window, you need to enter one command. However, that command depends on the .exe file.
If your .exe file is a regular personal information exchange file (PFX), type in.
SignTool sign /f YourCertFile.pfx ABCsoftware.exe
If you are using a .exe file that is a password-protected PFX file, type in.
SignTool sign /f YourCertFile.pfx /p AddYourPasswordHere ABCsoftware.exe
Now, when you are done with the mentioned steps, you have successfully signed the executable file.
Can you know if the EXE file is signed?
Yes, it is completely possible to know if the exe file is signed or not. Let’s take a look at the steps that you can follow to check the sign executable file.
- Go to the executable file and right-click on it.
- Select the “Properties” options at the bottom.
- The next screen will show you various tabs; choose the “Digital Certificates” tab.
- Look for a “Details” option on the Digital Certificates tab.
- Click on the “Details” option.
- Click on View Certificates, and there you can check the digital signature and its other aspects like Name, e-mail, and signing time.
Can a file be tampered with after signing?
Yes, an executable file can be tampered with after it has been signed. However, you don’t have to worry about it. When your PC compares the hash associated with the file, it will inform you if it does not match. You will get the warning message on the screen if the executable file is tampered with.
Timestamp the file while signing!
Just related to the previous topic, file tampering after signing, timestamping is the way to check if the file is tampered with or not. When you check the .exe file properties, you will see the time and date on which the software was digitally signed.
Therefore, if the file has been tampered with after it was signed, the computer will raise a warning. On the other hand, if the code signing certificate of the publisher has expired, the PC will verify the signature based on the time it was signed that executed. Hence, allowing it to run.
What is an Executable File and Code Signing Certificate?
Whenever you download software on your system, it can be in various formats. One of those formats, or should we say the extension is .exe. The executable or .exe file is an encoded sequence of instructions that the machine undertakes when the user clicks on it.
Usually, software or apps come with the .exe extension. However, there are other extensions, too, such as .bat, .dll, etc.
If we talk about the code signing certificate, it is a software security certificate used by app developers and publishers to sign their apps and software. Signing executable files with a code signing certificate promises software legitimacy and safety.
Why is Code Signing Necessary?
Well, we already know what code signing is, right? Let’s dive into the why factor!
Windows code signing deals with ensuring that the software program is legit. Here are some of the key pros of code signing!
Security of digital assets
One of the key benefits of code signing is that it promises the security of digital assets. How? Well, when the software code is signed by a digital certificate, it cannot be altered or changed. If the hash code used to sign the executable is the same as that of the downloaded application, the code integrity is intact. However, if the hash is not the same, the system will raise a warning for failing to download the code.
When a publisher develops an app, they sign it using a code signing certificate. This code signing certificate proves that the app comes from a trusted source. Users can also check the legitimacy of the app in its properties. Other than users, the digital signature also makes it easy for browsers and OS to verify the legitimacy.
Easy browser integration
If the .exe file software is signed by a code signing certificate, almost every browser will allow integration to it. Otherwise, all browsers block actions from unrecognized software.
Better user experience
It is obvious that if your software is digitally signed, which proves its legitimacy, there will be no unnecessary warning messages. Users will not face any inconvenience while using your software. Hence, enhancing their experience.
Faster time to market
To sign an executable file with the certificate, you need the certificate in the first place. And for that, you need to send some crucial documents to the certificate authority (CA). There are various certificate authorities on the web that require your business docs to ensure that you are legit. Once you get it, which is pretty fast as everything can be done online, your software is ready to hit the market.
Note: It usually takes around 1-3 days for standard code signing certificate and 1 – 5 days for EV code signing certificate to get issued.
So, this is all about how to sign an exe file. The core thing to understand here is that though it may not seem like a great deal, it can be dangerous if you don’t take care of Windows code signing. Code signing your executable software file can keep your software and applications safe from various issues. On top of all, it also ensures that your software is legit and will be accepted by users, browsers, and OSs alike.