"Your connection is not secure" Comodo For Home page

“Your connection is not secure” error appearing for sereval days now on Comodo For Home page.

Firefox error message:

antivirus.comodo.com uses an invalid security certificate. The certificate expired on Friday, 03 June, 2022 01:59. The current time is Friday, 24 June, 2022 17:00. Error code: SEC_ERROR_EXPIRED_CERTIFICATE

It happens on IPv4 only, IPv6 works.

Hi CISfan,

Could you please check now ?
Let us know your feedback.


Hello C.O.M.O.D.O RT,

Still the same error.
Firefox on Ipv4 cannot connect to https://antivirus.comodo.com/ on IPv6 it can.
I’ve tried on two systems with different Firefox versions but on both systems the same error on IPv4.

@ C.O.M.O.D.O RT
@ CISfan

W10 Famille - 21H1 - 19043.1746 / CFW :

I don’t have this problem.

Here it is still a problem.
IPv6 works IPv4 not.

The same issue happens on https://help.comodo.com/
Firefox on IPv4, “Your connection is not secure” or “Warning: Potential Security Risk Ahead”
Firefox on IPv6 works.

Same issue on https://personalfirewall.comodo.com/

Hi CISfan,

Thank you for reporting, we will check and update you.


The 1st link CISFan posted works for me in Firefox.

The other links don´t work in both Firefox and Google Chrome.

Hi all,

We have checked from our end and found no issues on this.
Refer the attached pics.
Kindly clear your browser caches and check.
If you found any issue kindly provide us with screenshot along with your location.


Just rebooted my system did clear dns cache and browser cache but the issue still persists on my end on all links posted previously.

I attach screenshot of https://antivirus.comodo.com/ the other posted links are same result.

Please also try TOR browser (on IPv4) using many different circuits and see what happens.

Hi CISfan,

We will check and update you.
May i know your location ?


@ C.O.M.O.D.O RT
@ CISfan
@ prallo

the return of virustotal on the 3 links.

I think the question is where do these expired / invalid site certificates come from which prevent me from having access to those 3 sites?

same result

Warning: Potential Security Risk Ahead

Firefox detected an issue and did not continue to antivirus.comodo.com. The website is either misconfigured or your computer clock is set to the wrong time.

It’s likely the website’s certificate is expired, which prevents Firefox from connecting securely. If you visit this site, attackers could try to steal information like your passwords, emails, or credit card details.

What can you do about it?

The issue is most likely with the website, and there is nothing you can do to resolve it. You can notify the website’s administrator about the problem.

and for Brave

Your connection is not private
Attackers might be trying to steal your information from antivirus.comodo.com (for example, passwords, messages, or credit cards). Learn more

it seems to happen for some european countries. I didn’t test them all…Comodo staff should…


this happens mainly when servers are under maintenance or certificates lose validity and are replaced, for example…

sorry my english!
Peace for all!

+1000000000. . .

Hi all,

We are checking on this .