An issue was discovered in Open XDMoD through 7.5.0. An authentication bypass (account takeover) exists due to a weak password reset mechanism. A brute-force attack against an MD5 rid value requires only 600 guesses in the plausible situation where the attacker knows that the victim has started a password-reset process (pass_reset.php, password_reset.php, XDUser.php) in the past few minutes.