CVE-2007-2249 : Détail

Le modèle EPSS produit un score de probabilité compris entre 0 et 1 (0 et 100 %). Plus la note est élevée, plus la probabilité qu'une vulnérabilité soit exploitée est grande.

Le percentile est utilisé pour classer les CVE en fonction de leur score EPSS. Par exemple, une CVE dans le 95e percentile selon son score EPSS est plus susceptible d'être exploitée que 95 % des autres CVE. Ainsi, le percentile sert à comparer le score EPSS d'une CVE par rapport à d'autres CVE.

source: https://www.securityfocus.com/bid/23616/info Phorum is prone to multiple input-validation vulnerabilities, including an unauthorized-access issue, privilege-escalation issue, multiple SQL-injection issues, and cross-site scripting issues, because the application fails to sufficiently sanitize user-supplied input. Exploiting these issues could allow an attacker to steal cookie-based authentication credentials, compromise the application, access or modify sensitive data, or exploit latent vulnerabilities in the underlying database implementation. Phorum 5.1.20 is affected; prior versions may also be vulnerable. All parameters must be set correctly for this exploit to work. "/control.php?1" --> "1" is forum id, where moderator has user moderation privileges. "user_ids[2]" --> "2" is userid of the user, who want's to get admin privileges And of course, moderator must be logged in before using exploit. It's that easy - you push the button - and you have admi rights!! So where is the initial problem for this security hole? Let's look at sourrce code of "include/controlcenter/users.php" line 29: ------------------[source code]---------------------- if(!empty($_POST["user_ids"])){ foreach($_POST["user_ids"] as $user_id){ if(!isset($_POST["approve"])){ $userdata["active"]=PHORUM_USER_INACTIVE; } else { $user=phorum_user_get($user_id); if($user["active"]==PHORUM_USER_PENDING_BOTH){ $userdata["active"]=PHORUM_USER_PENDING_EMAIL; } else { $userdata["active"]=PHORUM_USER_ACTIVE; // send reg approved message $maildata["mailsubject"]=$PHORUM["DATA"]["LANG"]["RegApprovedSubject"]; $maildata["mailmessage"]=wordwrap($PHORUM["DATA"]["LANG"]["RegApprovedEmailBody"], 72); phorum_email_user(array($user["email"]), $maildata); } } $userdata["user_id"]=$user_id; phorum_user_save($userdata); } } ------------------[/source code]---------------------- As we can see, by manipulating $_POST["user_ids"] parameter any user can be activated or deactivated. Including admin. So - there is no checking, if target user is allready active or has it higher privileges than moderator. This was mistake one. Now, mistake number two. Array "$userdata" is uninitialized. So we can "poison" that variable, if php settings has "register_globals=on". And in this way user moderator can deliver for saving any userdata for any user. For example - userdata[admin] carries user admin privileges. Solution: array initializing before use and adding some security checks.