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Forum Discussion

Rahul_More's avatar
Rahul_More
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Nov 11, 2020

"Illegal parameter value length" events when parameter is already at that value

Hi, The security policy is in transparent mode and when I enable block mode for site. The "Illegal parameter value length" logs are appearing in events request and the requested page is getting bloc...
application delivery
ASM Advanced WAF
security
Rahul_More's avatar
Rahul_More
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Nov 16, 2020

Hi Erik,

 

The detected parameter values are odd numbers (Ex. 5674) and when I accept the suggestion then maximum value length will get change from 1000 to 10000. except than "ctl00" there is no new suggestion currently available in traffic learning.

 

As per recommendation in bug report, I have disabled the "Learn from responses" feature and now I am monitoring the web application traffic and will ignore the suggestions if the value is lesser than applied one.

 

Kindly suggest if any other recommendations please.

 

 

Regards,

Rahul