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Forum Discussion

tminfw2's avatar
tminfw2
Icon for Nimbostratus rankNimbostratus
Jan 29, 2015

Bare byte decoding and French characters

Currently, our ASM policies are configured with bare byte decoding check activated. However, this poses problems, as some of our legitimate French pages are flagged with this error. Specifically, it ...
ASM Advanced WAF
management
security
tminfw2's avatar
tminfw2
Icon for Nimbostratus rankNimbostratus
Feb 26, 2015

In the meantime, I have found why we have this issue:

 

Suppose we have a page with a non-ASCII character in the url (Like http://www.test.com/identité.html). Clicking a link in this page would place the url in the referer field. Internet Explorer apparently puts the URL as it is. (Other browsers do a translation into ASCII characters) This triggers the log messages we see in our event log.

 

Do you need to take this fact into account when you want to check bare byte decoding? Do you need to whitelist URLs to achieve this?