How do you check if a PDF is safe?

Can a PDF file contain a virus?

Most of us consider PDF to be a safe file. It is true that PDF files appear to be a safer file type for documents compared to Word or Pages because it locks the document so that others cannot easily edit its content and is usually used in business, educational and personal fields. will be but what is important and we should be aware is that because most of us don't know that the PDF file has a virus and we use any kind of PDF, and that's why hackers make PDF files their main target.

How can a file contain a virus?

As mentioned above, PDF are the main target of viruses. They are the most common file type shared via email.Even though PDF are locked and no one can easily change or edit them, many of them usually have dynamic fields for forms or embedded signatures. These are dynamic and multimedia features that can be attacked by viruses and misused by malware and other vulnerabilities.In addition, it can be said that some PDF can contain JavaScript and it is one of the main channels for the distribution of malicious codes. If a PDF has the ability to execute system commands or contains multimedia, this is where a Systemic infection can hide.If you use a third-party app to open PDF, you may be exposed to risks.In order to solve these problems and reduce the attack of viruses, Adobe has disabled the ability to execute system commands in new and updated versions of Acrobat Reader. Keep in mind that if you're using older versions or other third-party software, it may still be active and causing you problems.

How to check PDF files for viruses?

One of the best ways to protect your Mac and system from PDF viruses is to download and open PDF files from known, reliable and trustworthy sources.But this solution cannot always be used. If you have to open a PDF that you received from an unknown person, you should scan the file for malware to detect viruses.Normally, email providers or Gmail will scan every email attachment and alert you if a malicious or Systemic infection is found. If your email provider does not have something like that, many antivirus apps can help you with this.

How is the system infected?

PDF viruses are usually spread via email or by drive downloads on malicious websites.Bad guys may trick you into opening attachments and clicking 'Enable Macros' or 'Enable Editing'. When you do this, you may see a message asking you to pay a large ransom to access your files. In such cases, the PDF has an attached document inside, which is usually an MS Word document. When you open the document using Adobe Acrobat Reader, the MS Word document opens and prompts you to enable editing via a social engineering attack: this executes a Visual Basic for Application macro that downloads the ransomware. and executes.Additionally, there are cases where a malicious website can use JavaScript or an applet to check for the presence of a PDF viewer plugin in your browser. By doing this, the malicious PDF containing the virus will be downloaded.

How to find out if the this file sent contains a virus?

Another way to determine if a PDF has a Systemic infection or not is to upload the file to Virus Total. But you should know that the results provided by Systemic Infection Total are not 100% accurate, but viruses can be detected to some extent.

Scan with X CleanMyMac

CleanMyMac X is an Apple-approved application designed to optimize your computer's performance.This application has an anti-malware module that can scan all the files on your hard disk and helps users to quickly identify and find and remove any viruses and malicious items.CleanMyMac X app is available for free and all users can download it for free. It goes without saying that using this application is very easy and simple.Once you have installed the CleanMyMac X application on your Mac, just follow the steps below:1.  Open the CleanMyMac X application2.  Click Remove Malware in the sidebar3.  Then click on Scan.These steps are all you need to do, and CleanMyMac X will do the rest. It'll let you know if it finds something it thinks you should remove, or else it'll let you know you're in clear mode.In general, if you find a PDF that you think is suspicious but nothing is found when you scan it, avoid opening it.

How to know if a file is safe or not?

In this context, it can be said that Adobe Acrobat provides an easy and productive way to share documents with others. It also provides security features to help protect the information contained in PDF. In some cases, you want to share a file but want to protect it from modification, copying and printing. It is also possible that the most sensitive files may be password protected so that anyone who has the password can view its contents and make any changes to it.

Files without password

Step 1. First, you need to run Adobe Acrobat Reader, then double-click the name of the Acrobat file you want to open.Step 2. Then select "Document Properties" from the "File" menu. In a window that appears on your screen, click on the "Security" tab.Step 3. In this step, it is necessary to check the security restrictions that have been applied to the document. To this end, read the "Document Security" summary at the top of the window for a complete explanation of the security restrictions applied to your files and documents. You can also read the "Summary of Document Restrictions" at the bottom of the window.Step 4. You need to notice the lock icon at the bottom of your document window. If this icon does not exist, it indicates that security files have not been applied to it.

Password protected files

Step 1. Run Acrobat Reader, then double-click the name of the Acrobat file you want to open.Step 2. Type the password in the box that appears on the screen.Step 3. Now you need to select "Document Properties" from the "File" menu, then click on the "Security" tab in the window that opens.Step 4. Now you need to check the restrictions applied on the file or document. Read the "Document Security" summary at the top of the window for a full explanation of the restrictions placed on the file.Step 5. Notice the lock icon at the bottom of your barrier window, which indicates that security rules apply to this PDF or document. Note that you cannot change the security of an Acrobat document using Adobe Reader.

Tips to protect your Mac from this type of file viruses

Read more about being careful with PDF above. But here are a few more tips to help keep your Mac safe from infected PDF files:1.  Disable JavaScript in your PDF readerDisabling JavaScript will prevent anything malicious lurking in the document from running the moment you open the file.Therefore, the good news here is that if you primarily use Preview to view PDF, you are in luck because it does not support JavaScript. To run JavaScript in a PDF, you need to open that file in the browser.But if you are using Adobe Reader or Adobe Acrobat, you have to do some things. Do these few steps:1.  Open Adobe Reader or Acrobat.2.  On the top toolbar, click Adobe Acrobat - Preferences.3.  Then select JavaScript in the sidebar.4.  Uncheck Enable Acrobat JavaScript to disable it completely.2.  Open the documents in your browser before downloadingIf you have the possibility to preview documents and PDF in your browser, you can save yourself from Systemic infection problems and its troubles. Therefore, if a file has a Systemic infection, it cannot spread to other files on your hard disk. The browser itself keeps everything, and it also saves less clutter on your Mac.It should be noted that if you accidentally or intentionally downloaded an infected PDF with a Systemic infection, it does not mean that it will immediately spread throughout your system. In general, to maintain more security and prevent viruses, it is recommended that you keep your security software up-to-date so that when you encounter a Systemic infection, it will be destroyed.

How can we download this type of files from the Internet safely?

When you want to download a free PDF from the Internet, it's no different than any other type of file, so if you're not sure who's hosting that file, it's best to avoid downloading and opening it if possible.

Additionally, consider some best practices:

•    If you received the PDF via email, be sure to remember to check the accompanying text carefully and if you trust the source, go ahead and download the file.•    If you are going to download a file from a website, make sure it is a trusted file and double check the exact address and make sure it is HTTPS.•    To download electronic books, look for university bookstores or reputable bookstores that offer them. Otherwise, you have to wait for bad consequences, i.e. Systemic infection and malicious items, and you have to scan them.

Result

It should be noted that whether the file is malicious or not does not depend on the file extension, that is, it does not matter if it is a PDF, but on the vulnerabilities of the software, that parses it. As a result, the PDF reader you are using contains a powerful buffer overflow vulnerability, then an attacker can easily create a special PDF to exploit that vulnerability.