Azure WAF rule 920470 blocking the requests with details massage: Pattern match ^[\w\d/\.\-\+]+(?:\s?;\s?(?:boundary|charset)\s?=\s?['"\w\d\.\-]+)?$ at REQUEST_HEADERS:content-type. But we excluded the rule like in the below snip still the rule blocking

Chandu 0

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Chandu 0 Reputation points

2024-08-01T12:57:49.39+00:00

Same rule excluded in lower environment it's working fine but in production we excluded the same but still we can see the blocked request by rule 920470
ChaitanyaNaykodi-MSFT 26,216 Reputation points Microsoft Employee

2024-08-02T02:27:30.85+00:00

@Chandu

Thank you for reaching out.

Can you please let us know the what is the value of content-type in your request here? if there is any un-supported character (eg ";") then this rule might get triggered.

Meanwhile can you update the match variable above to RequestHeaderValues as the request is blocked by the header value. More details here

Hope this helps! Thanks
Chandu 0 Reputation points

2024-08-05T10:51:18.0466667+00:00

@ChaitanyaNaykodi-MSFT

We have a form in our website once submitting that form this rule is blocking, I have checked in the developer tools in network tab for the request headers it is showing the value Content-Type.

For me the form getting submitted while checking in the logs i saw some requests are blocked because of this rule 920470. but as mentioned in above images we have excluded the rule for Request header keys: Contains: Content-Type.

Still i observed some requests blocked. Pls assist me on this how can we fix this issue?
ChaitanyaNaykodi-MSFT 26,216 Reputation points Microsoft Employee

2024-08-30T00:51:31.9933333+00:00

@Chandu

Thank you for getting back and apologies for the delayed response here.

but as mentioned in above images we have excluded the rule for Request header keys: Contains: Content-Type.

Instead of Request header keys did you try using **RequestHeaderValues.**If yes, then a support request will be required here to resolve the issue. If you do not have a support plan please let me know. Thank you!

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Azure WAF rule 920470 blocking the requests with details massage: Pattern match ^[\w\d/\.\-\+]+(?:\s?;\s?(?:boundary|charset)\s?=\s?['"\w\d\.\-]+)?$ at REQUEST_HEADERS:content-type. But we excluded the rule like in the below snip still the rule blocking

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