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Forum Discussion

Aurel's avatar
Aurel
Icon for Cirrus rankCirrus
Feb 12, 2019

Content-Type header in body

Hello guys, I have an application that behaves not really RFC compliant, crafting request with Content-Type header after a CRLF. The request is a multipart/form-data.   ASM is then considering thi...
ASM Advanced WAF
security
samstep_81205's avatar
samstep_81205
Icon for Nimbostratus rankNimbostratus
Mar 04, 2019

RFC violation is pretty serious and the risks are quite high - just Google for "CRLF Injection" to see the dangers of such attacks.

 

You should really speak to application developers to get them to fix this and remove the CRLF injection vulnerability. If fixing the application code is not possible then you need to very carefully consider the exception - you might need to do it with an iRule and only allow the exception from Trusted IP address rather than the whole Internet.