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query-stringquerystringparametermalformed

Recognize the pattern: what system is malforming my query string parameters?


We have a fairly complicated ASP.NET MVC project with cross domain login widgets and a lot of semi-legacy code.

There is a system where we login people through an iframe. The url for the iframe we send through a string attached to the MVC Model.

Problem is; on really rare occassions we see malformed query string parameters coming through. It's always the same malformation though. I want to fix the issue, but I can't figure out why this happens.

I'm expecting some Adblocker-type or privacy settings, or maybe some Regional settings, but I have no clue where to start.

I am hoping someone will recognize the pattern and say; that's a localization pattern when your Windows is set on Turkey or whatever, you should check your encoding etc etc.

Anyway here's the example:

Expected:
    auth-dialog-window?openerOrigin=https%3a%2f%2f.poules.com&color=C3042E&openerType=iframe
Coming through:
    auth-dialog-window?color=P304212R&openerType=vsenzr&openerOrigin=uggcf%3N%2S%2Scbhyrf.pbz

Apparently the order of the query string also changes. Here more closely per parameter:

iframe
vsenzr

https://      poules.com (spaces are for aligning)
uggcf%3N%2S%2Scbhyrf.pbz

C3042E
P304212R

Does anyone recognize the pattern and can give me a hint where I should be looking?

I know for sure the last time it happened with IE 9.0, but can't reproduce it.


Solution

  • ROT-13.

    A system somewhere is "trying to crypt" in a very simple way...

    Check "pairs" of letters in both values:

    abcdefghijklmnopqrstuvwxyzabcdefghijklm
    nopqrstuvwxyzabcdefghijklmnopqrstuvwxyz