You have a URL injection bug. You took a arbitrary text (a base64 string) and used it as a url parameter value without first converting it into a url parameter value. This is the same class of problem which are exploited by SQL injection attacks.

Whenever one interpolates a string into another or concatenate a string with another, one needs to consider whether any conversion is required. Concatenating strings could very well be the biggest security risk of the times. People forget they're not just concatenating strings; they're concatenating the content of those strings.


In reply to Re: CGI-class changes + to space for BASE64-data by ikegami
in thread CGI-class changes + to space for BASE64-data by Pickwick

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