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Forbidden 403

  • Cavab yoxdur
  • 0 have this problem
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Hello support.

We have a job that runs every hour pinging a service. From 28th of August each hour we recieve several error emails.

Every querry that is re run completes normally. We can not figure out what the issue is.

We have checked everything on our side.

I have captured tcpdump on the server and found this in wireshark.

[1 bytes missing in capture file].GET http://detectportal.firefox.com/canonical.html HTTP/1.1 Host: detectportal.firefox.com User-Agent: Mozilla/5.0 (X11; Ubuntu; Linux x86_64; rv:109.0) Gecko/20100101 Firefox/116.0 Accept: */* Accept-Language: en-US,en;q=0.5 Accept-Encoding: gzip, deflate Cache-Control: no-cache Pragma: no-cache Connection: keep-alive


HTTP/1.1 403 Forbidden Mime-Version: 1.0 Date: Thu, 12 Sep 2024 11:39:24 CEST Content-Type: text/html Connection: keep-alive Proxy-Connection: keep-alive Content-Length: 2346

<meta http-equiv="Content-Type" content="text/html; charset=UTF-8"> <title>Notification: Policy: URL Filtering</title> <style type="text/css"> body { font-family: Arial, Helvetica, sans-serif; font-size: 14px; color:#333333; background-color: #ffffff; } h1 { font-size: 18px; font-weight: bold; text-decoration: none; padding-top: 0px; color: #2970A6; } a:link { color: #2970A6; text-decoration: none; } a:hover { color: #2970A6; text-decoration: underline; } p.buttonlink { margin-bottom: 24px; } .copyright { font-size: 12px; color: #666666; margin: 5px 5px 0px 30px; } .details { font-size: 14px; color: #969696; border: none; padding: 20px 20px 20px 20px; margin: 0px 10px 10px 35px; } .shadow { border: 3px solid #9f9f9f; padding: 10px 25px 10px 25px; margin: 10px 35px 0px 30px; background-color: #ffffff; width: 600px; -moz-box-shadow: 3px 3px 3px #cccccc; -webkit-box-shadow: 3px 3px 3px #cccccc; box-shadow: 3px 3px 3px #cccccc; /* For IE 8 */ -ms-filter: "progid:DXImageTransform.Microsoft.Shadow(Strength=5, Direction=135, Color='cccccc')"; /* For IE 5.5 - 7 */ filter: progid:DXImageTransform.Microsoft.Shadow(Strength=5, Direction=135, Color='cccccc'); } .logo { border: none; margin: 5px 5px 0px 30px; } </style>

 

This Page Cannot Be Displayed

Based on your organization's access policies, access to this web site ( http://detectportal.firefox.com/canonical.html ) has been blocked because the web category "Infrastructure and Content Delivery Networks" is not allowed.

PROXY-06

If you have questions, please contact Sys Support and provide the codes shown below.

Date: Thu, 12 Sep 2024 11:39:24 CEST
Username:
Source IP: 10.9.56.105
URL: GET http://detectportal.firefox.com/canonical.html
Category: Infrastructure and Content Delivery Networks
Reason: BLOCK-WEBCAT
Notification: WEBCAT

GET http://detectportal.firefox.com/canonical.html HTTP/1.1 Host: detectportal.firefox.com User-Agent: Mozilla/5.0 (X11; Ubuntu; Linux x86_64; rv:109.0) Gecko/20100101 Firefox/116.0 Accept: */* Accept-Language: en-US,en;q=0.5 Accept-Encoding: gzip, deflate Cache-Control: no-cache Pragma: no-cache Connection: keep-alive


HTTP/1.1 403 Forbidden Mime-Version: 1.0 Date: Thu, 12 Sep 2024 11:39:24 CEST Content-Type: text/html Connection: keep-alive Proxy-Connection: keep-alive Content-Length: 2346

<meta http-equiv="Content-Type" content="text/html; charset=UTF-8"> <title>Notification: Policy: URL Filtering</title> <style type="text/css"> body { font-family: Arial, Helvetica, sans-serif; font-size: 14px; color:#333333; background-color: #ffffff; } h1 { font-size: 18px; font-weight: bold; text-decoration: none; padding-top: 0px; color: #2970A6; } a:link { color: #2970A6; text-decoration: none; } a:hover { color: #2970A6; text-decoration: underline; } p.buttonlink { margin-bottom: 24px; } .copyright { font-size: 12px; color: #666666; margin: 5px 5px 0px 30px; } .details { font-size: 14px; color: #969696; border: none; padding: 20px 20px 20px 20px; margin: 0px 10px 10px 35px; } .shadow { border: 3px solid #9f9f9f; padding: 10px 25px 10px 25px; margin: 10px 35px 0px 30px; background-color: #ffffff; width: 600px; -moz-box-shadow: 3px 3px 3px #cccccc; -webkit-box-shadow: 3px 3px 3px #cccccc; box-shadow: 3px 3px 3px #cccccc; /* For IE 8 */ -ms-filter: "progid:DXImageTransform.Microsoft.Shadow(Strength=5, Direction=135, Color='cccccc')"; /* For IE 5.5 - 7 */ filter: progid:DXImageTransform.Microsoft.Shadow(Strength=5, Direction=135, Color='cccccc'); } .logo { border: none; margin: 5px 5px 0px 30px; } </style>

 

This Page Cannot Be Displayed

Based on your organization's access policies, access to this web site ( http://detectportal.firefox.com/canonical.html ) has been blocked because the web category "Infrastructure and Content Delivery Networks" is not allowed.

PROXY-06

If you have questions, please contact Sys Support and provide the codes shown below.

Date: Thu, 12 Sep 2024 11:39:24 CEST
Username:
Source IP: 10.9.56.105
URL: GET http://detectportal.firefox.com/canonical.html
Category: Infrastructure and Content Delivery Networks
Reason: BLOCK-WEBCAT
Notification: WEBCAT

GET http://detectportal.firefox.com/canonical.html HTTP/1.1 Host: detectportal.firefox.com User-Agent: Mozilla/5.0 (X11; Ubuntu; Linux x86_64; rv:109.0) Gecko/20100101 Firefox/116.0 Accept: */* Accept-Language: en-US,en;q=0.5 Accept-Encoding: gzip, deflate Cache-Control: no-cache Pragma: no-cache Connection: keep-alive


HTTP/1.1 403 Forbidden Mime-Version: 1.0 Date: Thu, 12 Sep 2024 11:39:24 CEST Content-Type: text/html Connection: keep-alive Proxy-Connection: keep-alive Content-Length: 2346

<meta http-equiv="Content-Type" content="text/html; charset=UTF-8"> <title>Notification: Policy: URL Filtering</title> <style type="text/css"> body { font-family: Arial, Helvetica, sans-serif; font-size: 14px; color:#333333; background-color: #ffffff; } h1 { font-size: 18px; font-weight: bold; text-decoration: none; padding-top: 0px; color: #2970A6; } a:link { color: #2970A6; text-decoration: none; } a:hover { color: #2970A6; text-decoration: underline; } p.buttonlink { margin-bottom: 24px; } .copyright { font-size: 12px; color: #666666; margin: 5px 5px 0px 30px; } .details { font-size: 14px; color: #969696; border: none; padding: 20px 20px 20px 20px; margin: 0px 10px 10px 35px; } .shadow { border: 3px solid #9f9f9f; padding: 10px 25px 10px 25px; margin: 10px 35px 0px 30px; background-color: #ffffff; width: 600px; -moz-box-shadow: 3px 3px 3px #cccccc; -webkit-box-shadow: 3px 3px 3px #cccccc; box-shadow: 3px 3px 3px #cccccc; /* For IE 8 */ -ms-filter: "progid:DXImageTransform.Microsoft.Shadow(Strength=5, Direction=135, Color='cccccc')"; /* For IE 5.5 - 7 */ filter: progid:DXImageTransform.Microsoft.Shadow(Strength=5, Direction=135, Color='cccccc'); } .logo { border: none; margin: 5px 5px 0px 30px; } </style>

 

This Page Cannot Be Displayed

Based on your organization's access policies, access to this web site ( http://detectportal.firefox.com/canonical.html ) has been blocked because the web category "Infrastructure and Content Delivery Networks" is not allowed.

PROXY-06

If you have questions, please contact Sys Support and provide the codes shown below.

Date: Thu, 12 Sep 2024 11:39:24 CEST
Username:
Source IP: 10.9.56.105
URL: GET http://detectportal.firefox.com/canonical.html
Category: Infrastructure and Content Delivery Networks
Reason: BLOCK-WEBCAT
Notification: WEBCAT

GET http://detectportal.firefox.com/canonical.html HTTP/1.1 Host: detectportal.firefox.com User-Agent: Mozilla/5.0 (X11; Ubuntu; Linux x86_64; rv:109.0) Gecko/20100101 Firefox/116.0 Accept: */* Accept-Language: en-US,en;q=0.5 Accept-Encoding: gzip, deflate Cache-Control: no-cache Pragma: no-cache Connection: keep-alive


HTTP/1.1 403 Forbidden Mime-Version: 1.0 Date: Thu, 12 Sep 2024 11:39:24 CEST Content-Type: text/html Connection: keep-alive Proxy-Connection: keep-alive Content-Length: 2346

<meta http-equiv="Content-Type" content="text/html; charset=UTF-8"> <title>Notification: Policy: URL Filtering</title> <style type="text/css"> body { font-family: Arial, Helvetica, sans-serif; font-size: 14px; color:#333333; background-color: #ffffff; } h1 { font-size: 18px; font-weight: bold; text-decoration: none; padding-top: 0px; color: #2970A6; } a:link { color: #2970A6; text-decoration: none; } a:hover { color: #2970A6; text-decoration: underline; } p.buttonlink { margin-bottom: 24px; } .copyright { font-size: 12px; color: #666666; margin: 5px 5px 0px 30px; } .details { font-size: 14px; color: #969696; border: none; padding: 20px 20px 20px 20px; margin: 0px 10px 10px 35px; } .shadow { border: 3px solid #9f9f9f; padding: 10px 25px 10px 25px; margin: 10px 35px 0px 30px; background-color: #ffffff; width: 600px; -moz-box-shadow: 3px 3px 3px #cccccc; -webkit-box-shadow: 3px 3px 3px #cccccc; box-shadow: 3px 3px 3px #cccccc; /* For IE 8 */ -ms-filter: "progid:DXImageTransform.Microsoft.Shadow(Strength=5, Direction=135, Color='cccccc')"; /* For IE 5.5 - 7 */ filter: progid:DXImageTransform.Microsoft.Shadow(Strength=5, Direction=135, Color='cccccc'); } .logo { border: none; margin: 5px 5px 0px 30px; } </style>

 

This Page Cannot Be Displayed

Based on your organization's access policies, access to this web site ( http://detectportal.firefox.com/canonical.html ) has been blocked because the web category "Infrastructure and Content Delivery Networks" is not allowed.

PROXY-06

If you have questions, please contact Sys Support and provide the codes shown below.

Date: Thu, 12 Sep 2024 11:39:24 CEST
Username:
Source IP: 10.9.56.105
URL: GET http://detectportal.firefox.com/canonical.html
Category: Infrastructure and Content Delivery Networks
Reason: BLOCK-WEBCAT
Notification: WEBCAT

GET http://detectportal.firefox.com/canonical.html HTTP/1.1 Host: detectportal.firefox.com User-Agent: Mozilla/5.0 (X11; Ubuntu; Linux x86_64; rv:109.0) Gecko/20100101 Firefox/116.0 Accept: */* Accept-Language: en-US,en;q=0.5 Accept-Encoding: gzip, deflate Cache-Control: no-cache Pragma: no-cache Connection: keep-alive


HTTP/1.1 403 Forbidden Mime-Version: 1.0 Date: Thu, 12 Sep 2024 11:39:24 CEST Content-Type: text/html Connection: keep-alive Proxy-Connection: keep-alive Content-Length: 2346

<meta http-equiv="Content-Type" content="text/html; charset=UTF-8"> <title>Notification: Policy: URL Filtering</title> <style type="text/css"> body { font-family: Arial, Helvetica, sans-serif; font-size: 14px; color:#333333; background-color: #ffffff; } h1 { font-size: 18px; font-weight: bold; text-decoration: none; padding-top: 0px; color: #2970A6; } a:link { color: #2970A6; text-decoration: none; } a:hover { color: #2970A6; text-decoration: underline; } p.buttonlink { margin-bottom: 24px; } .copyright { font-size: 12px; color: #666666; margin: 5px 5px 0px 30px; } .details { font-size: 14px; color: #969696; border: none; padding: 20px 20px 20px 20px; margin: 0px 10px 10px 35px; } .shadow { border: 3px solid #9f9f9f; padding: 10px 25px 10px 25px; margin: 10px 35px 0px 30px; background-color: #ffffff; width: 600px; -moz-box-shadow: 3px 3px 3px #cccccc; -webkit-box-shadow: 3px 3px 3px #cccccc; box-shadow: 3px 3px 3px #cccccc; /* For IE 8 */ -ms-filter: "progid:DXImageTransform.Microsoft.Shadow(Strength=5, Direction=135, Color='cccccc')"; /* For IE 5.5 - 7 */ filter: progid:DXImageTransform.Microsoft.Shadow(Strength=5, Direction=135, Color='cccccc'); } .logo { border: none; margin: 5px 5px 0px 30px; } </style>

 

This Page Cannot Be Displayed

Based on your organization's access policies, access to this web site ( http://detectportal.firefox.com/canonical.html ) has been blocked because the web category "Infrastructure and Content Delivery Networks" is not allowed.

PROXY-06

If you have questions, please contact Sys Support and provide the codes shown below.

Date: Thu, 12 Sep 2024 11:39:24 CEST
Username:
Source IP: 10.9.56.105
URL: GET http://detectportal.firefox.com/canonical.html
Category: Infrastructure and Content Delivery Networks
Reason: BLOCK-WEBCAT
Notification: WEBCAT

GET http://detectportal.firefox.com/canonical.html HTTP/1.1 Host: detectportal.firefox.com User-Agent: Mozilla/5.0 (X11; Ubuntu; Linux x86_64; rv:109.0) Gecko/20100101 Firefox/116.0 Accept: */* Accept-Language: en-US,en;q=0.5 Accept-Encoding: gzip, deflate Cache-Control: no-cache Pragma: no-cache Connection: keep-alive


HTTP/1.1 403 Forbidden Mime-Version: 1.0 Date: Thu, 12 Sep 2024 11:39:24 CEST Content-Type: text/html Connection: keep-alive Proxy-Connection: keep-alive Content-Length: 2346

<meta http-equiv="Content-Type" content="text/html; charset=UTF-8"> <title>Notification: Policy: URL Filtering</title> <style type="text/css"> body { font-family: Arial, Helvetica, sans-serif; font-size: 14px; color:#333333; background-color: #ffffff; } h1 { font-size: 18px; font-weight: bold; text-decoration: none; padding-top: 0px; color: #2970A6; } a:link { color: #2970A6; text-decoration: none; } a:hover { color: #2970A6; text-decoration: underline; } p.buttonlink { margin-bottom: 24px; } .copyright { font-size: 12px; color: #666666; margin: 5px 5px 0px 30px; } .details { font-size: 14px; color: #969696; border: none; padding: 20px 20px 20px 20px; margin: 0px 10px 10px 35px; } .shadow { border: 3px solid #9f9f9f; padding: 10px 25px 10px 25px; margin: 10px 35px 0px 30px; background-color: #ffffff; width: 600px; -moz-box-shadow: 3px 3px 3px #cccccc; -webkit-box-shadow: 3px 3px 3px #cccccc; box-shadow: 3px 3px 3px #cccccc; /* For IE 8 */ -ms-filter: "progid:DXImageTransform.Microsoft.Shadow(Strength=5, Direction=135, Color='cccccc')"; /* For IE 5.5 - 7 */ filter: progid:DXImageTransform.Microsoft.Shadow(Strength=5, Direction=135, Color='cccccc'); } .logo { border: none; margin: 5px 5px 0px 30px; } </style>

 

This Page Cannot Be Displayed

Based on your organization's access policies, access to this web site ( http://detectportal.firefox.com/canonical.html ) has been blocked because the web category "Infrastructure and Content Delivery Networks" is not allowed.

PROXY-06

If you have questions, please contact Sys Support and provide the codes shown below.

Date: Thu, 12 Sep 2024 11:39:24 CEST
Username:
Source IP: 10.9.56.105
URL: GET http://detectportal.firefox.com/canonical.html
Category: Infrastructure and Content Delivery Networks
Reason: BLOCK-WEBCAT
Notification: WEBCAT


What is the cause of this? And how can we prevent it.

Thank you in advance.

KR, Nikola

Hello support. We have a job that runs every hour pinging a service. From 28th of August each hour we recieve several error emails. Every querry that is re run completes normally. We can not figure out what the issue is. We have checked everything on our side. I have captured tcpdump on the server and found this in wireshark. [1 bytes missing in capture file].GET http://detectportal.firefox.com/canonical.html HTTP/1.1 Host: detectportal.firefox.com User-Agent: Mozilla/5.0 (X11; Ubuntu; Linux x86_64; rv:109.0) Gecko/20100101 Firefox/116.0 Accept: */* Accept-Language: en-US,en;q=0.5 Accept-Encoding: gzip, deflate Cache-Control: no-cache Pragma: no-cache Connection: keep-alive HTTP/1.1 403 Forbidden Mime-Version: 1.0 Date: Thu, 12 Sep 2024 11:39:24 CEST Content-Type: text/html Connection: keep-alive Proxy-Connection: keep-alive Content-Length: 2346 <!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd"> <html> <head> <meta http-equiv="Content-Type" content="text/html; charset=UTF-8"> <title>Notification: Policy: URL Filtering</title> <style type="text/css"> body { font-family: Arial, Helvetica, sans-serif; font-size: 14px; color:#333333; background-color: #ffffff; } h1 { font-size: 18px; font-weight: bold; text-decoration: none; padding-top: 0px; color: #2970A6; } a:link { color: #2970A6; text-decoration: none; } a:hover { color: #2970A6; text-decoration: underline; } p.buttonlink { margin-bottom: 24px; } .copyright { font-size: 12px; color: #666666; margin: 5px 5px 0px 30px; } .details { font-size: 14px; color: #969696; border: none; padding: 20px 20px 20px 20px; margin: 0px 10px 10px 35px; } .shadow { border: 3px solid #9f9f9f; padding: 10px 25px 10px 25px; margin: 10px 35px 0px 30px; background-color: #ffffff; width: 600px; -moz-box-shadow: 3px 3px 3px #cccccc; -webkit-box-shadow: 3px 3px 3px #cccccc; box-shadow: 3px 3px 3px #cccccc; /* For IE 8 */ -ms-filter: "progid:DXImageTransform.Microsoft.Shadow(Strength=5, Direction=135, Color='cccccc')"; /* For IE 5.5 - 7 */ filter: progid:DXImageTransform.Microsoft.Shadow(Strength=5, Direction=135, Color='cccccc'); } .logo { border: none; margin: 5px 5px 0px 30px; } </style> </head> <body> <div class="logo"><img src="http://www.zgh.hr/UserDocsImages/slike/logotipi-holding/zgh.jpg" border="0"></div><p>&nbsp;</p> <div class="shadow"> <h1>This Page Cannot Be Displayed</h1> <p> Based on your organization's access policies, access to this web site (&nbsp;http://detectportal.firefox.com/canonical.html&nbsp;) has been blocked because the web category &quot;Infrastructure and Content Delivery Networks&quot; is not allowed. </p> <p>PROXY-06</p> <p> </p> <p> If you have questions, please contact Sys Support and provide the codes shown below. </p> <div> </div> </div> <div class="details"><p> Date: Thu, 12 Sep 2024 11:39:24 CEST<br /> Username: <br /> Source IP: 10.9.56.105<br /> URL: GET http://detectportal.firefox.com/canonical.html<br /> Category: Infrastructure and Content Delivery Networks<br /> Reason: BLOCK-WEBCAT<br /> Notification: WEBCAT </p></div> </body> </html> GET http://detectportal.firefox.com/canonical.html HTTP/1.1 Host: detectportal.firefox.com User-Agent: Mozilla/5.0 (X11; Ubuntu; Linux x86_64; rv:109.0) Gecko/20100101 Firefox/116.0 Accept: */* Accept-Language: en-US,en;q=0.5 Accept-Encoding: gzip, deflate Cache-Control: no-cache Pragma: no-cache Connection: keep-alive HTTP/1.1 403 Forbidden Mime-Version: 1.0 Date: Thu, 12 Sep 2024 11:39:24 CEST Content-Type: text/html Connection: keep-alive Proxy-Connection: keep-alive Content-Length: 2346 <!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd"> <html> <head> <meta http-equiv="Content-Type" content="text/html; charset=UTF-8"> <title>Notification: Policy: URL Filtering</title> <style type="text/css"> body { font-family: Arial, Helvetica, sans-serif; font-size: 14px; color:#333333; background-color: #ffffff; } h1 { font-size: 18px; font-weight: bold; text-decoration: none; padding-top: 0px; color: #2970A6; } a:link { color: #2970A6; text-decoration: none; } a:hover { color: #2970A6; text-decoration: underline; } p.buttonlink { margin-bottom: 24px; } .copyright { font-size: 12px; color: #666666; margin: 5px 5px 0px 30px; } .details { font-size: 14px; color: #969696; border: none; padding: 20px 20px 20px 20px; margin: 0px 10px 10px 35px; } .shadow { border: 3px solid #9f9f9f; padding: 10px 25px 10px 25px; margin: 10px 35px 0px 30px; background-color: #ffffff; width: 600px; -moz-box-shadow: 3px 3px 3px #cccccc; -webkit-box-shadow: 3px 3px 3px #cccccc; box-shadow: 3px 3px 3px #cccccc; /* For IE 8 */ -ms-filter: "progid:DXImageTransform.Microsoft.Shadow(Strength=5, Direction=135, Color='cccccc')"; /* For IE 5.5 - 7 */ filter: progid:DXImageTransform.Microsoft.Shadow(Strength=5, Direction=135, Color='cccccc'); } .logo { border: none; margin: 5px 5px 0px 30px; } </style> </head> <body> <div class="logo"><img src="http://www.zgh.hr/UserDocsImages/slike/logotipi-holding/zgh.jpg" border="0"></div><p>&nbsp;</p> <div class="shadow"> <h1>This Page Cannot Be Displayed</h1> <p> Based on your organization's access policies, access to this web site (&nbsp;http://detectportal.firefox.com/canonical.html&nbsp;) has been blocked because the web category &quot;Infrastructure and Content Delivery Networks&quot; is not allowed. </p> <p>PROXY-06</p> <p> </p> <p> If you have questions, please contact Sys Support and provide the codes shown below. </p> <div> </div> </div> <div class="details"><p> Date: Thu, 12 Sep 2024 11:39:24 CEST<br /> Username: <br /> Source IP: 10.9.56.105<br /> URL: GET http://detectportal.firefox.com/canonical.html<br /> Category: Infrastructure and Content Delivery Networks<br /> Reason: BLOCK-WEBCAT<br /> Notification: WEBCAT </p></div> </body> </html> GET http://detectportal.firefox.com/canonical.html HTTP/1.1 Host: detectportal.firefox.com User-Agent: Mozilla/5.0 (X11; Ubuntu; Linux x86_64; rv:109.0) Gecko/20100101 Firefox/116.0 Accept: */* Accept-Language: en-US,en;q=0.5 Accept-Encoding: gzip, deflate Cache-Control: no-cache Pragma: no-cache Connection: keep-alive HTTP/1.1 403 Forbidden Mime-Version: 1.0 Date: Thu, 12 Sep 2024 11:39:24 CEST Content-Type: text/html Connection: keep-alive Proxy-Connection: keep-alive Content-Length: 2346 <!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd"> <html> <head> <meta http-equiv="Content-Type" content="text/html; charset=UTF-8"> <title>Notification: Policy: URL Filtering</title> <style type="text/css"> body { font-family: Arial, Helvetica, sans-serif; font-size: 14px; color:#333333; background-color: #ffffff; } h1 { font-size: 18px; font-weight: bold; text-decoration: none; padding-top: 0px; color: #2970A6; } a:link { color: #2970A6; text-decoration: none; } a:hover { color: #2970A6; text-decoration: underline; } p.buttonlink { margin-bottom: 24px; } .copyright { font-size: 12px; color: #666666; margin: 5px 5px 0px 30px; } .details { font-size: 14px; color: #969696; border: none; padding: 20px 20px 20px 20px; margin: 0px 10px 10px 35px; } .shadow { border: 3px solid #9f9f9f; padding: 10px 25px 10px 25px; margin: 10px 35px 0px 30px; background-color: #ffffff; width: 600px; -moz-box-shadow: 3px 3px 3px #cccccc; -webkit-box-shadow: 3px 3px 3px #cccccc; box-shadow: 3px 3px 3px #cccccc; /* For IE 8 */ -ms-filter: "progid:DXImageTransform.Microsoft.Shadow(Strength=5, Direction=135, Color='cccccc')"; /* For IE 5.5 - 7 */ filter: progid:DXImageTransform.Microsoft.Shadow(Strength=5, Direction=135, Color='cccccc'); } .logo { border: none; margin: 5px 5px 0px 30px; } </style> </head> <body> <div class="logo"><img src="http://www.zgh.hr/UserDocsImages/slike/logotipi-holding/zgh.jpg" border="0"></div><p>&nbsp;</p> <div class="shadow"> <h1>This Page Cannot Be Displayed</h1> <p> Based on your organization's access policies, access to this web site (&nbsp;http://detectportal.firefox.com/canonical.html&nbsp;) has been blocked because the web category &quot;Infrastructure and Content Delivery Networks&quot; is not allowed. </p> <p>PROXY-06</p> <p> </p> <p> If you have questions, please contact Sys Support and provide the codes shown below. </p> <div> </div> </div> <div class="details"><p> Date: Thu, 12 Sep 2024 11:39:24 CEST<br /> Username: <br /> Source IP: 10.9.56.105<br /> URL: GET http://detectportal.firefox.com/canonical.html<br /> Category: Infrastructure and Content Delivery Networks<br /> Reason: BLOCK-WEBCAT<br /> Notification: WEBCAT </p></div> </body> </html> GET http://detectportal.firefox.com/canonical.html HTTP/1.1 Host: detectportal.firefox.com User-Agent: Mozilla/5.0 (X11; Ubuntu; Linux x86_64; rv:109.0) Gecko/20100101 Firefox/116.0 Accept: */* Accept-Language: en-US,en;q=0.5 Accept-Encoding: gzip, deflate Cache-Control: no-cache Pragma: no-cache Connection: keep-alive HTTP/1.1 403 Forbidden Mime-Version: 1.0 Date: Thu, 12 Sep 2024 11:39:24 CEST Content-Type: text/html Connection: keep-alive Proxy-Connection: keep-alive Content-Length: 2346 <!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd"> <html> <head> <meta http-equiv="Content-Type" content="text/html; charset=UTF-8"> <title>Notification: Policy: URL Filtering</title> <style type="text/css"> body { font-family: Arial, Helvetica, sans-serif; font-size: 14px; color:#333333; background-color: #ffffff; } h1 { font-size: 18px; font-weight: bold; text-decoration: none; padding-top: 0px; color: #2970A6; } a:link { color: #2970A6; text-decoration: none; } a:hover { color: #2970A6; text-decoration: underline; } p.buttonlink { margin-bottom: 24px; } .copyright { font-size: 12px; color: #666666; margin: 5px 5px 0px 30px; } .details { font-size: 14px; color: #969696; border: none; padding: 20px 20px 20px 20px; margin: 0px 10px 10px 35px; } .shadow { border: 3px solid #9f9f9f; padding: 10px 25px 10px 25px; margin: 10px 35px 0px 30px; background-color: #ffffff; width: 600px; -moz-box-shadow: 3px 3px 3px #cccccc; -webkit-box-shadow: 3px 3px 3px #cccccc; box-shadow: 3px 3px 3px #cccccc; /* For IE 8 */ -ms-filter: "progid:DXImageTransform.Microsoft.Shadow(Strength=5, Direction=135, Color='cccccc')"; /* For IE 5.5 - 7 */ filter: progid:DXImageTransform.Microsoft.Shadow(Strength=5, Direction=135, Color='cccccc'); } .logo { border: none; margin: 5px 5px 0px 30px; } </style> </head> <body> <div class="logo"><img src="http://www.zgh.hr/UserDocsImages/slike/logotipi-holding/zgh.jpg" border="0"></div><p>&nbsp;</p> <div class="shadow"> <h1>This Page Cannot Be Displayed</h1> <p> Based on your organization's access policies, access to this web site (&nbsp;http://detectportal.firefox.com/canonical.html&nbsp;) has been blocked because the web category &quot;Infrastructure and Content Delivery Networks&quot; is not allowed. </p> <p>PROXY-06</p> <p> </p> <p> If you have questions, please contact Sys Support and provide the codes shown below. </p> <div> </div> </div> <div class="details"><p> Date: Thu, 12 Sep 2024 11:39:24 CEST<br /> Username: <br /> Source IP: 10.9.56.105<br /> URL: GET http://detectportal.firefox.com/canonical.html<br /> Category: Infrastructure and Content Delivery Networks<br /> Reason: BLOCK-WEBCAT<br /> Notification: WEBCAT </p></div> </body> </html> GET http://detectportal.firefox.com/canonical.html HTTP/1.1 Host: detectportal.firefox.com User-Agent: Mozilla/5.0 (X11; Ubuntu; Linux x86_64; rv:109.0) Gecko/20100101 Firefox/116.0 Accept: */* Accept-Language: en-US,en;q=0.5 Accept-Encoding: gzip, deflate Cache-Control: no-cache Pragma: no-cache Connection: keep-alive HTTP/1.1 403 Forbidden Mime-Version: 1.0 Date: Thu, 12 Sep 2024 11:39:24 CEST Content-Type: text/html Connection: keep-alive Proxy-Connection: keep-alive Content-Length: 2346 <!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd"> <html> <head> <meta http-equiv="Content-Type" content="text/html; charset=UTF-8"> <title>Notification: Policy: URL Filtering</title> <style type="text/css"> body { font-family: Arial, Helvetica, sans-serif; font-size: 14px; color:#333333; background-color: #ffffff; } h1 { font-size: 18px; font-weight: bold; text-decoration: none; padding-top: 0px; color: #2970A6; } a:link { color: #2970A6; text-decoration: none; } a:hover { color: #2970A6; text-decoration: underline; } p.buttonlink { margin-bottom: 24px; } .copyright { font-size: 12px; color: #666666; margin: 5px 5px 0px 30px; } .details { font-size: 14px; color: #969696; border: none; padding: 20px 20px 20px 20px; margin: 0px 10px 10px 35px; } .shadow { border: 3px solid #9f9f9f; padding: 10px 25px 10px 25px; margin: 10px 35px 0px 30px; background-color: #ffffff; width: 600px; -moz-box-shadow: 3px 3px 3px #cccccc; -webkit-box-shadow: 3px 3px 3px #cccccc; box-shadow: 3px 3px 3px #cccccc; /* For IE 8 */ -ms-filter: "progid:DXImageTransform.Microsoft.Shadow(Strength=5, Direction=135, Color='cccccc')"; /* For IE 5.5 - 7 */ filter: progid:DXImageTransform.Microsoft.Shadow(Strength=5, Direction=135, Color='cccccc'); } .logo { border: none; margin: 5px 5px 0px 30px; } </style> </head> <body> <div class="logo"><img src="http://www.zgh.hr/UserDocsImages/slike/logotipi-holding/zgh.jpg" border="0"></div><p>&nbsp;</p> <div class="shadow"> <h1>This Page Cannot Be Displayed</h1> <p> Based on your organization's access policies, access to this web site (&nbsp;http://detectportal.firefox.com/canonical.html&nbsp;) has been blocked because the web category &quot;Infrastructure and Content Delivery Networks&quot; is not allowed. </p> <p>PROXY-06</p> <p> </p> <p> If you have questions, please contact Sys Support and provide the codes shown below. </p> <div> </div> </div> <div class="details"><p> Date: Thu, 12 Sep 2024 11:39:24 CEST<br /> Username: <br /> Source IP: 10.9.56.105<br /> URL: GET http://detectportal.firefox.com/canonical.html<br /> Category: Infrastructure and Content Delivery Networks<br /> Reason: BLOCK-WEBCAT<br /> Notification: WEBCAT </p></div> </body> </html> GET http://detectportal.firefox.com/canonical.html HTTP/1.1 Host: detectportal.firefox.com User-Agent: Mozilla/5.0 (X11; Ubuntu; Linux x86_64; rv:109.0) Gecko/20100101 Firefox/116.0 Accept: */* Accept-Language: en-US,en;q=0.5 Accept-Encoding: gzip, deflate Cache-Control: no-cache Pragma: no-cache Connection: keep-alive HTTP/1.1 403 Forbidden Mime-Version: 1.0 Date: Thu, 12 Sep 2024 11:39:24 CEST Content-Type: text/html Connection: keep-alive Proxy-Connection: keep-alive Content-Length: 2346 <!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd"> <html> <head> <meta http-equiv="Content-Type" content="text/html; charset=UTF-8"> <title>Notification: Policy: URL Filtering</title> <style type="text/css"> body { font-family: Arial, Helvetica, sans-serif; font-size: 14px; color:#333333; background-color: #ffffff; } h1 { font-size: 18px; font-weight: bold; text-decoration: none; padding-top: 0px; color: #2970A6; } a:link { color: #2970A6; text-decoration: none; } a:hover { color: #2970A6; text-decoration: underline; } p.buttonlink { margin-bottom: 24px; } .copyright { font-size: 12px; color: #666666; margin: 5px 5px 0px 30px; } .details { font-size: 14px; color: #969696; border: none; padding: 20px 20px 20px 20px; margin: 0px 10px 10px 35px; } .shadow { border: 3px solid #9f9f9f; padding: 10px 25px 10px 25px; margin: 10px 35px 0px 30px; background-color: #ffffff; width: 600px; -moz-box-shadow: 3px 3px 3px #cccccc; -webkit-box-shadow: 3px 3px 3px #cccccc; box-shadow: 3px 3px 3px #cccccc; /* For IE 8 */ -ms-filter: "progid:DXImageTransform.Microsoft.Shadow(Strength=5, Direction=135, Color='cccccc')"; /* For IE 5.5 - 7 */ filter: progid:DXImageTransform.Microsoft.Shadow(Strength=5, Direction=135, Color='cccccc'); } .logo { border: none; margin: 5px 5px 0px 30px; } </style> </head> <body> <div class="logo"><img src="http://www.zgh.hr/UserDocsImages/slike/logotipi-holding/zgh.jpg" border="0"></div><p>&nbsp;</p> <div class="shadow"> <h1>This Page Cannot Be Displayed</h1> <p> Based on your organization's access policies, access to this web site (&nbsp;http://detectportal.firefox.com/canonical.html&nbsp;) has been blocked because the web category &quot;Infrastructure and Content Delivery Networks&quot; is not allowed. </p> <p>PROXY-06</p> <p> </p> <p> If you have questions, please contact Sys Support and provide the codes shown below. </p> <div> </div> </div> <div class="details"><p> Date: Thu, 12 Sep 2024 11:39:24 CEST<br /> Username: <br /> Source IP: 10.9.56.105<br /> URL: GET http://detectportal.firefox.com/canonical.html<br /> Category: Infrastructure and Content Delivery Networks<br /> Reason: BLOCK-WEBCAT<br /> Notification: WEBCAT </p></div> </body> </html> What is the cause of this? And how can we prevent it. Thank you in advance. KR, Nikola
Attached screenshots

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