NGINX Forbidden error while redirecting to external site

[vaishali_valavade]

Hi all,

I am a newbie to Adobe Experience Platform.

We have setup our own Cookie Dialog for our website. 

And are using Adobe Analytics to track the visitor data. There is one scenario in which when a user clicks on the button (say. Take me to "xxx") he is redirected to an external site.

Now the events are getting tracked for the Page Views, button clicks etc. But when we hit the above button, instead of redirecting to the external URL, we get a NGINX Forbidden error. If we disable the analytics on the site, it works fine.

Can someone explain what might be happening?

[Gokul_Agiwal]

Hi @vaishali_valavade 

NGINX is a web server for web serving, reverse proxying, caching, load balancing, media streaming, and more. It started out as a web server designed for maximum performance and stability. 

forbidden errors are caused by an access misconfiguration on the client-side. so  you need to check your configuration settings or access permissions, check what's happening on button click. So this is nothing about AEP. 

This general guide might help you https://linuxhint.com/fix-nginx-403-forbidden/ 

Hope this helps.

[tim_funk]

When you have the forbidden error - check your browser console for all the cookies set for that domain. 

Cookies are sent from the browser to the (web) server for things like state management.

The sum size of all the cookie header sent by the browser is too large for the server (as configured) to handle.

The "solution" is to use less cookies or smaller ones. (for that domain). If these are cookies beyond you control, such as they are set by Adobe Analytics - You may need to open a support ticket for Adobe to advice an new solution based on your configuraiton.

[vaishali_valavade]

Thanks. Still getting the error.

Logs state:

{"info"=>"Warning. detected XSS using libinjection.", "file"=>"/etc/nginx/owasp-modsecurity-crs/rules/REQUEST-941-APPLICATION-ATTACK-XSS.conf", "line"=>"37", "id"=>"941100", "rev"=>"", "msg"=>"XSS Attack Detected via libinjection", "data"=>"Matched Data: XSS data found within REQUEST_COOKIES:s_sq: 

And my s_sq cookie is

abc%3D%2526c.%2526a.%2526activitymap.%2526page%253Dhttps%25253A%25252F%25252Fxyz.com%25252F%2526link%253DCONTINUE%2526region%253DBODY%2526.activitymap%2526.a%2526.c%2526pid%253Dhttps%25253A%25252F%25252Fxyz.com%25252F%2526oid%253DfunctionHa%252528%252529%25257B%25257D%2526oidt%253D2%2526ot%253DSUBMIT

Can you tell me whats wrong with this? 

Note: have changed the name of the domain

[Gokul_Agiwal]

Hi @vaishali_valavade 

s_sq cookie is related to ClickMap/Activity map. As your log info shows the 

"msg"=>"XSS Attack Detected via libinjection", "data"=>"Matched Data: XSS data found within REQUEST_COOKIES:s_sq: 

As per the scenario you're seeing the issues when user clicks on the button and navigate to external site so there might be possibility of that issues so 

Try removing Activity Map module from the Analytics and then see you still seeing the error. 

To remove Activity Map - Follow the below steps. 

If you implemented Analytics extension through Launch then 

Go To Adobe Launch (Data Collection) -> Select the Web Property -> Extensions-> Chose Adobe Analytics -> Configure-> deselect Use Activity Map checkbox. 

in case if you implemented analytics using custom method then look for below 

function AppMeasurement_Module_ActivityMap()  and remove it.

Let us know if this works and we troubleshoot further.

hope this helps. 

[vaishali_valavade]

Thanks for the quick reply.

We need the Activity map for analytics data. Its already being used in the analytics dashboard. Is there a way we can know what in the cookie is causing the error?

[Gokul_Agiwal]

Hi @vaishali_valavade 

it's bit tricky to see the value set into s_sq cookie when you click on the element and the action set on that element

The s_sq cookies are set and read under AppMeasurement code so I don't think so anything that checks s_sq cookies on server side. However in analytics extension itself we can have the option to Write secure cookies. Can you please check if that option is enabled at your end. This is helpful when your implementation served securely over https.

And the option I had suggested before to remove activity map - I think you can make a change on your development local environment right and you can able to see if any differences 

[vaishali_valavade]

Hi gokula

The "Write Secure cookies" option is already enabled.

Just another question.. I have installed the Chrome debugger for Adobe Analytics..

And in that it shows the following entry which also appears in the REQUEST_COOKIE s_sq above

ClickMap ObjectId : functionHa(){}

I went through the AppMeasurement js file and have no where found the reference to this function..Can you please let me know if this is correct? or is this the reason its causing the nginx error

Also in Adobe Launch, theres a feature "Enable ClickMap" - What is this used for?

[Gokul_Agiwal · Accepted solution]

Hi @vaishali_valavade 

Enable ClickMap is plugin mainly for IE and Firefox browser and module for report and analytics. Ultimately it does the same job like ActivityMap. 

When any clickable element is clicked data will be stored in a cookie named s_sq.

Now I'm not sure which debugger you downloaded for however you can also download the activity map extension for browser and check if that works correctly for you so that you can identified the issues.

If that not works then I would suggest to remove activity map functionality completely in local environment and see difference. 

Hope this helps to troubleshoot again. 

[adobechat]

Is the re-direct URL a sub-domain on where the popup is hosted or is it external site? Saying that, I think this is more likely a Client-Server issue rather than anything to do with Adobe Experience Platform.