An internal link shared from one account, if accessed from a different account redirects to a random location, rather than giving an error message.
To reproduce:
Generate an internal link for some file (doesn’t matter which) of your account, send it to another user (on the same server, where the other user has a different account) who opens it with his/her credentials (different from yours). This other user will be redirected to a random location within his/her file-system, rather than receiving an error messge informing him/her that he/she didn’t enter the correct credentials.
This behaviour generated unpredictable results and confusion among the user community.