Hi all,

Following KES 12.11.0 deployment, our users are getting an ERR_TOO_MANY_REDIRECTS errors when trying to access specific web sites. I have confirmed that it is browser independent and definitely related to the Web Threat Protection component. Adding site exceptions and/or changing other various parameters in the Web Threat Protection settings don not make a difference - the only thing that works is disabling Web Threat Protection completely.

Has anyone else experienced this and do you have any insights / suggested fixes?

Thanks,
Doug

16 hours ago, Gone Phishing said:

Hi all,

Following KES 12.11.0 deployment, our users are getting an ERR_TOO_MANY_REDIRECTS errors when trying to access specific web sites. I have confirmed that it is browser independent and definitely related to the Web Threat Protection component. Adding site exceptions and/or changing other various parameters in the Web Threat Protection settings don not make a difference - the only thing that works is disabling Web Threat Protection completely.

Has anyone else experienced this and do you have any insights / suggested fixes?

Thanks,
Doug

Can you please share some screenshot of the errors or warning. 

The issue is intermittent (as in it happens maybe 50% of the time) and occurs when we attempt to access any of the four URLs below:

https://workforcenow.adp.com
https://login.payworks.ca/login
https://collaboration.geowarehouse.ca/ui/login-with-okta
https://secure.paymentech.com/portal/por_new.aspx

It happens in three different browsers (Firefox, Edge and Chrome), all with cookies and history freshly cleared. Attached are a couple of screenshots from different browsers on different sites when the error does come up. It only happens with KES 12.11 (12.11.0.637) - KES 12.10 (12.10.0.466) works fine (I manually uninstalled KES 12.11 on a few PCs and they again work just fine again with KES 12.10). It happens on three different versions of Windows (Win 11 Pro 25H2, Win 11 Pro 23H2, Win 10 Pro 22H2), all fully patched.

I am unfortunately unable to downgrade the KES client through the administration server, and manually uninstalling KES 12.11 on 100+ systems is not exactly an option.

Thanks & best regards,

Doug

 

I am also getting this error in australia

with Commbank.com.au

exiting & stopping kaspersky completely allows this webpage to display normally

 

Please note... im not using any VPN's whatsoever

 

im using v21.23.6.614 of Kaspersky Plus

 

 

 

 

Yes, when I completely exit / terminate the KES 12.11 client the sites also load correctly. If I just disable all protection but the KES client is still running on the system, I still can't access them. No VPNs here either.

At least one of the sites that we're having issues with - and I see that the one you're having trouble accessing is also finance-related as are three of the four that we noticed it with - redirects specific information to Okta for the user authentication. I am not sure about the other ones.

I don't know if the above is in any way relevant to Kaspersky support, but I thought I'd post it here for their information.

im feeling at least relived its not just me!!

ive logged a ticket with Kaspersky...... in the hope they can resolve this ....

seems like Kaspersky is abit aggressive with legit sites!

Edited November 19, 2025Nov 19 by David-W

so the issue seems to be "Safe Browsing" - I switched it off... rebooted and it now works!

so it seems the "Safe Browsing" is being over protective

I also switched "Safe Browsing" on and then I drilled down further and switched off the "URL Advisor" - seemed to still work ok

 

are you able to replicate @Gone Phishing

Edited November 20, 2025Nov 20 by David-W

31 minutes ago, David-W said:

so the issue seems to be "Safe Browsing" - I switched it off... rebooted and it now works!

so it seems the "Safe Browsing" is being over protective

I also switched "Safe Browsing" on and then I drilled down further and switched off the "URL Advisor" - seemed to still work ok

 

are you able to replicate @Gone Phishing

further investigation - I think its the "Safe Browsing" causing the issues.... switch it off... seems to stop the err_too_many_redirects

There is no Safe Browsing option in the managed Kaspersky Endpoint Security client, but there is a Web Protection component, and yes, turning that off in the policy for all the computers in the container on the admin server and restarting them does allow access as I mentioned in my original post. However, that would be a case of the cure being (considerably) worse than the disease... Web Protection is essential as there's hardly a day when some employee does not come across an infected web site that could easily result in a company-wide breach and/or take down the entire network. It's not really an option to turn off Web Protection any more than it is to turn off Kaspersky entirely.

6 hours ago, Gone Phishing said:

There is no Safe Browsing option in the managed Kaspersky Endpoint Security client, but there is a Web Protection component, and yes, turning that off in the policy for all the computers in the container on the admin server and restarting them does allow access as I mentioned in my original post. However, that would be a case of the cure being (considerably) worse than the disease... Web Protection is essential as there's hardly a day when some employee does not come across an infected web site that could easily result in a company-wide breach and/or take down the entire network. It's not really an option to turn off Web Protection any more than it is to turn off Kaspersky entirely.

Sorry!  im only trying to help Id the cause of the issue... im a home user.... whos having the same issues!

1 hour ago, David-W said:

Sorry!  im only trying to help Id the cause of the issue... im a home user.... whos having the same issues!

No apology needed - every little bit of information helps.

I contacted Kaspersky support today by phone and spoke with a nice and knowledgeable rep... he knew what I was referring to and told me to add exemptions for the specific URLs in a place I would not have thought to look, which fixed the issue.

In an enterprise environment with an administration server, in the policy for the applicable container for the computers, it is under General settings -> Network settings -> under the Encrypted connections scan section there is a Configure trusted addresses button where you can enter not just specific IP addresses but also domain URLs including wildcard characters (e.g. *.problemwebsite.com). You have to list the affected domains individually, but after you save the changes to the policy and the changes propagate to the affected machines, the sites are again accessible.

I also use Kaspersky on my personal computers. While I am not experiencing the issue with the home-grade antivirus (21.23.6.614), the equivalent settings would be under Settings (the gear icon at the bottom left of the of application window) -> Security settings -> Advanced protection -> Advanced settings -> Network settings -> under the Encrypted connections scan section there is a Configure trusted addresses link where you can enter the domain URLs. As I said, my home machines were not affected, but that is the equivalent setting on the Kaspersky home product I use.

Just to add to this, we also started seeing this after updating a small number of test users to KES to 12.11 using KSC.

Unfortunately it decided to do this to our Webmail providers URL..

I was able to add the affected URLs to the trusted URL's section (and also allowed them in Web Control > Allowed for good measure).

Hoping Kaspersky can fix this fairly quickly, as I have paused the roll out until it is sorted. I don't fancy 300 endpoints all calling me to say a different URL they use daily is now not working..

 

1 hour ago, Minty said:

Just to add to this, we also started seeing this after updating a small number of test users to KES to 12.11 using KSC.

Unfortunately it decided to do this to our Webmail providers URL..

I was able to add the affected URLs to the trusted URL's section (and also allowed them in Web Control > Allowed for good measure).

Hoping Kaspersky can fix this fairly quickly, as I have paused the roll out until it is sorted. I don't fancy 300 endpoints all calling me to say a different URL they use daily is now not working..

 

I just heard back from Kaspersky support.

It appears there will not be a fix rolled out for this, and we should just add URL's to the Trusted URL's section of KSC.

I just hope this doesn't affect too many URL's going forward, or it is going to be a busy end to the year!

2 hours ago, Minty said:

I just heard back from Kaspersky support.

It appears there will not be a fix rolled out for this, and we should just add URL's to the Trusted URL's section of KSC.

I just hope this doesn't affect too many URL's going forward, or it is going to be a busy end to the year!

Thanks for the update. Interesting to know that Kaspersky won't be pushing out a fix.

I have two different medium-size clients (50-100 endpoints each) using Kaspersky, and there have been a total of five affected sites between them. Four of the five affected portals are financial services / HR / payroll companies, and only one something else that uses "serious" authentication. Hope the number also remains low for you.

Cheers,
Doug

Kaspersky support informed me otherwise, stating that a version update will be released soon to address this issue.

 

Edited November 28, 2025Nov 28 by Andrew Loh

On 11/28/2025 at 11:39 PM, Andrew Loh said:

Kaspersky support informed me otherwise, stating that a version update will be released soon to address this issue.

 

Hmm, that is confusing.

This was the response I got:

Quote

Please refer to the solution in the Forum link you mentioned.

Of course each new product release has changes, improvements and other fixes so it is not unusual if something will not work as expected as it was before in a previous version.

The solution from Forum will solve the problem you reported.

 

Edited December 1, 2025Dec 1 by Minty

hi there!

i can confirm

a lot of sites impacted

banca intesa

gefran

and many more

 

a bounce of sites

i cannot do an exception for all these sites

error is random, sometimes doesn't works, sometimes works perfectly

wait for a fix

Edited December 1, 2025Dec 1 by Igioz

The workaround is effective, but it shouldn’t be considered a permanent fix IMO.

yes workaround works
but
is not a solution

Hello together,

the issue with too many redirects can be workarounded by exclusions or setting the option "Decrypt an encrypted connection with the website that uses EV certificate "
https://support.kaspersky.com/help/KESWin/12.11/en-us/175124.htm

This behavior is in progress by RnD and it will be fixed soon independend from the workaround given.
Unfortunately there is no time frame when it is fixed. So the current solution is to use the workaround.

 

The application patch appears to have resolved the issue in my initial testing.

where i can find that patch?

1 minute ago, Igioz said:

where i can find that patch?

I believe you can obtain the patch from the Kaspersky support ticket. 

Hello together,

it is true that a private fix is available to fix this issue since today. However, as the name said it is a private fix which will be provided individually per incident. So to get the patch you have to open a ticket with Technical Support.

Please provide a description and a screenshot of the problem when opening the ticket anyway to classify it.

I assume the fix will be implemented in next release. Refer to the release notes once a new Release will be announced.

Thank you in advance
Best Regards

 

 

I now understand that this issue is related to Chromium’s implementation of UDP (QUIC/HTTPS over UDP). By sending encrypted packets over UDP without the traditional handshake, HTTPS connections become significantly faster. However, in a corporate environment where hundreds of users are browsing multiple websites simultaneously, this can lead to packet mix-ups and errors. Therefore, it seems the problem is not caused by Kaspersky ?  Am I correct ?

 

Hello,

could be but needs a support ticket to analyze and determine it correctly.

Best Regards