Azure Application Gateway
An Azure service that provides a platform-managed, scalable, and highly available application delivery controller as a service.
1,172 questions
Umbraco cookie authentication not working with UMB_UCONTEXT_C
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Developer
0
Reputation points
Hello,
We are using an application developed in Umbraco 10.
We have configured Azure WAF but noticed that the umbraco backoffice does not work. Backoffice use UMB_UCONTEXT_C and values are alphanumeric with special characters and having (_) and (-) as well.
A similar type of issue has been reported here
https://github.com/MicrosoftDocs/azure-docs/issues/94465
The WAF used is version 2.
Any suggestion?
{count} votes
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GitaraniSharma-MSFT 49,886 Reputation points Microsoft Employee2023-07-31T12:32:35.46+00:00 Hello @Developer ,
Welcome to Microsoft Q&A Platform. Thank you for reaching out & hope you are doing well.
Could you please let me know what is the OWASP version used in your WAF? Is it 3.2, 3.1, 3.0?
Also, could you please share the WAF log for this request which is blocking it?
From what I've seen in the past, Umbraco backoffice triggers the following ruleId": "200004" - "Multipart parser detected a possible unmatched boundary."
Rule 200004 means that the WAF engine noticed a line in the form/multipart input that resembled a multipart boundary. This mostly happens when there is a parsing error in the JSON (due to an invalid character).
And the general recommendation is to disable this rule "200004 - Possible Multipart Unmatched Boundary".
Regards,
Gita
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Developer 0 Reputation points
2023-08-01T07:55:37.7966667+00:00 Hi,
We have tried 3 possible comibinations
Workaround 1 :-
- I have disabled the default OWASP Rule "200004 - Possible Multipart Unmatched Boundary"
- WAF Policy was in Prevention mode
- Still, an umbraco application loaded with blank page (issue is still persist)
Workaround 2 :-
- I have disabled the default OWASP Rule "200004 - Possible Multipart Unmatched Boundary"
- I have moved WAF Policy to Detection Mode
- I have Disabled the WAF Policy
- Still, an umbraco application loaded with blank page (issue is still persist)
Workaround 3 :-
- I have disabled all the default OWASP Rule
- I have moved WAF Policy to Detection Mode
- I have Disabled the WAF Policy
- Still, an umbraco application loaded with blank page (issue is still persist)
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GitaraniSharma-MSFT 49,886 Reputation points Microsoft Employee
2023-08-01T14:50:01.0266667+00:00 Thank you for the update, @Developer .
Since you've already tried the possible workarounds and the issue persists, we may need to look into the backend logs and would need access to your resources for further investigation. So, if you have a support plan, I request you file a support ticket, else please do let us know, we will try and help you get a one-time free technical support.
In case you need help with a one-time free technical support, please send an email with subject line "ATTN gishar | Umbraco cookie authentication not working with UMB_UCONTEXT_C" to AzCommunity[at]Microsoft[dot]com with the following details, I will follow-up with you.
- Reference this Q&A thread
- Your Azure Subscription ID
Note: Do not share any PII data as a public comment.
We will post a summarized answer once the issue is resolved.
Regards,
Gita
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GitaraniSharma-MSFT 49,886 Reputation points Microsoft Employee
2023-08-08T13:28:56.2766667+00:00 @Developer , could you please provide an update on this post? In case you need help with a one-time free technical support, please send an email as advised above.
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