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Avoid session ID leakages


The system must not expose session IDs in URLs and messages presented to the user.


Session IDs are sensitive information that may allow an attacker to steal, modify and/or destroy information once they obtain one. Information sent via URL parameters is:

  • stored in clear text in the browser history. sent to external sites via the referrer HTTP header.

  • sent to external sites via the search bar if the browser interprets the URL as a query.

  • visible to scripts running on the browser that may belong to third-parties.

Therefore, session IDs should not be sent via URL parameters, nor be displayed as messages presented to the user, nor stored in logs.