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Forum Discussion

KarimBenyelloul's avatar
KarimBenyelloul
Icon for Cirrostratus rankCirrostratus
Jan 23, 2019

Malformed JSON data and Character encoding

Hi team, The following POST request triggers the violation "Malformed JSON data" . POST https://10.10.1.80/ HTTP/1.1 Content-Type: application/json; charset=iso-8859-1 Host: 10.10.1.80 Expect: 10...
ASM Advanced WAF
security
samstep's avatar
samstep
Icon for Cirrocumulus rankCirrocumulus
Jan 23, 2019

ASM is correct in blocking this request as JSON can't be encoded in charset= iso-8859-1

 

The JSON Standard (RFC7159) clearly states that:

 

"JSON text shall be encoded in UTF-8, UTF-16, or UTF-32"

 

Speak to the application developers as they should be sending JSON in UTF-8 and escaping the special characters. If they question this - point them to the JSON standard.

 

Link to JSON Standard: https://tools.ietf.org/html/rfc7159