Probléme de sécurité

<?php
	session_start();
		if(isset($_SESSION['pseudo']))
		{
	 		Echo '<a>Bonjour </a>';
			echo $_SESSION['pseudo'];
			echo '</br>';
			echo '<a href="../scripts/php/deco.php">Deconection</a>';
			echo '</br>';
			echo '<a href="home.html">Home</a>';
		
			echo '
			</br></br></br>
	
			<a>News</a>
			</br>
			<FORM method="POST" action="../scripts/php/ajoutnews.php">
 				<P>Titre:<br>
 					<INPUT type="text" name="titre" size=30>
 				</p>
 				<P>Numero:<br>
 					<INPUT type="text" name="nbnews" size=30>
 				</p>
 				<P>Contenu:<br>
 					<INPUT type="text" name="contenu" size=30>
 				</p>
 				<INPUT type="submit" value="Ajouter la News">
			</form>
		
			';	
		}
		
		else
			echo'			
				<a href="home.html">Home</a>
				</br>
				
				<FORM method="POST" action="../scripts/php/actionlog.php">
					
					<P>Login<br>
						<input type="text" name="login" value="" size="20" id="login"/>
					<br>
					</p>
					<P>Mot de passe<br>
					<input type="password" name="mdp" value="" size="20" MAXLENGTH="15" id="mdp"/>
						</p>	
				<INPUT type="submit" value="connection"/>
				</FORM>	
				';	
									
?>

<?php
	include('logbd.php');
	
	$jour=date(d);
	$mois=date(m);
	$annee=date(Y);
	$heure=date(H);
	$minute=date(i);
	$titre=$_POST['titre'];
	$contenu=$_POST['contenu'];
	$nbnews=$_POST['nbnews'];


	mysql_query ("INSERT INTO news VALUES ('', '$jour', '$mois', '$annee', '$heure', '$minute', '$titre', '$contenu', '$nbnews')");

	echo '<a>La news a bien ete ajouter.</a>';
	echo '<meta http-equiv="refresh" content="2; URL=../../pages/admin.php">';

?> 

<?php
mysql_connect("adresse", "login", "mdp");
		mysql_select_db("mdp");
?>