Mozilla_Pkix_Error_Mitm_Detected Firefox

Error 491 Play Store
Error 491 Play Store


“MOZILLA PKIX ERROR MITM DETECTED Error on Firefox” is displayed in this section.

Mozilla Firefox is still one of the most frequently used web browsers on the market today, according to the latest statistics. Its beta testers complimented the program’s security, responsiveness, and efficiency of its add-ons. However, it is not without flaws, just like any other browser. A large number of Firefox users are experiencing difficulties seeing websites with HTTPS prefixes, with the majority of them encountering the following errors:

When you see this message, it means that your browser does not trust the certificates supplied by websites that you visit. The good news is that there is still a chance to gain access. Here’s how to resolve the ‘MOZILLA PKIX ERROR MITM DETECTED’ error message.

Check see this related article: How can you fix the Corrupted Content Error when accessing Gmail?
The following is a table of contents:
So, what exactly is an error message stating that “MOZILLA PKIX Error Mitm Detected” means?


The problem here is that your network or system is interfering with your connection and certificates. Certificates are therefore distrusted by Firefox as a result. This occurs when malware attempts to replace a legitimate certificate with one that it has created. You must have dependable security software installed on your computer in order to stop this problem from occurring.

Auslogics Anti-Malware is one of various antivirus solutions available, but it is the only one that provides total protection. As well as scanning your browser extensions and system memory for potentially malicious applications, it also prevents data leakage and detects threats to the security of your machine.


The Nightly version of Firefox was the one that was most frequently reported as having the problem. In this case, utilise a stable build to gain access to password-protected websites. You can also learn how to resolve security error codes on secure websites using Firefox if it doesn’t work for you the first time. The procedures are as follows:

Method 1: Disable HTTPS Scanning

Changes can be made to the security settings of any antivirus product. Consequently, if your security software checks HTTPS, disable it. This trait is known by a variety of names, including:

Ensure that SSL is in place.
Don’t scan links that are encrypted.
Solutions that are risk-free

Method 2: Disabling HTTPS Scanning in Firefox

It is not recommended to disable HTTPS screening in Firefox. This is the last resort for dealing with ‘MOZILLA PKIX ERROR MITM DETECTED’ problems.

Fire up Mozilla Firefox on your computer.
In the URL field, type “about:config” (without the quotations).
Then, when an information message appears, choose ‘I accept the risk!’
Look for the security.enterprise roots.enabled variable.
Were you able to locate it and double-click on it?
Set it to the value ‘true.
Restart Firefox to make the changes take effect.
Follow the steps outlined above if you want to import custom certificates from other security software products installed on your computer. Consequently, the sources can now be trusted, and the error ‘MOZILLA PKIX ERROR MITM DETECTED’ is no longer displayed.

User Questions:

Learn how to turn off the ‘Microsoft Edge is being used for sharing’ pop-up window as well:
User Inquiries: What should I do if I receive a security certificate error warning in the Mozilla Firefox web browser?
Click Alternatively, you might include an exception on the error page.
From the drop-down box, select Add Exception to your rule.
Make a selection from the drop-down option that says “Get Certificate.”
To see a window that describes the issue with your z/OSMF site, select View from the menu bar.
When you’ve finished checking the certificate, close the dialogue box.
Select the Confirm Security Exception checkbox to indicate that you trust the z/OSMF site.
What can I do to fix Firefox if it is not resolving any potential security issues?
Continue to rely on a poor internet connection.
Please add this site to the list of trusted sites.
For the time being, turn off your antivirus and firewall software.
It is necessary to clear the SSL State.
Delete Your Browsing History from Your Computer
Allow Firefox to rely on root authority to function properly.
Change the security settings on your computer.
What is Mozilla pkix error mitm detected and how can I fix it?
Seeing the error codes SEC ERROR UNKNOWN ISSUER or MOZILLA PKIX ERROR MITM DETECTED on a “Warning: Potential Security Risk Ahead” warning page signifies that the certificate provided was issued by a certificate authority that Firefox does not recognise and, as a result, cannot be trusted by the browser.

The following steps will guide you through the process of resetting Mozilla Firefox.
Select “Apps” from the “Settings” menu on your smartphone after opening it.
Locate and launch the Firefox application.
“Storage” can be selected from the drop-down menu.
“Manage Space” can be found under the drop-down menu.
The option “Clear all data” should be used.
To confirm your decision, use the “Ok” button.
Take a look at these more resources: Instructions on how to fix your Firefox connection is not secure problem
What is it about Firefox that makes it so blind to potential security flaws?
Because of an incorrect system date, Firefox may detect that a website’s security certificate has expired or is no longer valid. Check to see that the date, time, and time zone on your computer are correct. For more information, see How to solve time-related problems on secure websites for more information.