In the module “Xen Forum” (xenforum) edited by App1pro, an authenticated user can perform SQL injection in affected versions. 2.13.0 fixed vulnerabilities.

Summary

  • CVE ID: CVE-2023-24763
  • Published at: 2023-03-06
  • Advisory source: Friends-of-Presta.org
  • Platform: PrestaShop
  • Product: xenforum
  • Impacted release: < 2.13.0
  • Product author: App1pro
  • Weakness: CWE-89
  • Severity: high (8.8)

Description

In Xen Forum module for PrestaShop up to 2.13.0, multiple sensitives SQL calls in class XenForumAttachment::getListAttachments() (or XenForumCat, XenForumPost, …) can be executed with a trivial http call and exploited to forge a bind SQL injection.

CVSS base metrics

  • Attack vector: network
  • Attack complexity: low
  • Privilege required: low
  • User interaction: none
  • Scope: unchanged
  • Confidentiality: high
  • Integrity: high
  • Availability: high

Vector string: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H

Possible malicious usage

  • Technical and personal data leaks
  • Obtain admin access
  • Remove all data of the linked PrestaShop
  • Display sensitives tables to front-office to unlock potential admin’s ajax scripts of modules protected by token on the ecosystem

Proof of concept

curl -v --cookie-jar cookie.txt 'https://domain.tld/authentification?submitLogin=1&emailXXXX&password=YYY && \
curl -v --cookie cookie.txt 'http://domain.tld/index.php?fc=module&module=xenforum&id=194&controller=editpost&edit_post=1&attachments[]=3%29%3BSELECT%20SLEEP%2825%29%23'

Patch

--- a/classes/XenForumAttachment.php
+++ b/classes/XenForumAttachment.php
@@ -55,7 +55,7 @@ class XenForumAttachment extends ObjectM
     public static function getListAttachments($ids)
     {
         $sql = 'SELECT *, id_xenforum_attachment as id
-            FROM '._DB_PREFIX_.'xenforum_attachment WHERE id_xenforum_attachment IN ('.implode(',', $ids).');';
+            FROM '._DB_PREFIX_.'xenforum_attachment WHERE id_xenforum_attachment IN ('.implode(', ', array_map('intval', $ids)).');';
         return DB::getInstance()->executeS($sql);
     }
 }
diff -bpru a/classes/XenForumCat.php b/classes/XenForumCat.php
--- a/classes/XenForumCat.php
+++ b/classes/XenForumCat.php
@@ -60,7 +60,7 @@ class XenForumCat extends ObjectModel
             $ql .= ' AND (pc.`private` = 0';
             // Allow this user access to private forum
             if (!empty($validations)) {
-                $ql .= ' OR pc.`id_xenforum_cat` IN ('.pSQL($validations).')';
+                $ql .= ' OR pc.`id_xenforum_cat` IN ('.implode(', ', array_map('intval', $validations)).')';
             }
             $ql .= ')';
         }
@@ -82,7 +82,7 @@ class XenForumCat extends ObjectModel
             if (empty($availables)) {
                 return false;
             }
-            $sql .= ' AND pc.`id_xenforum_cat` IN ('.pSQL(implode(',', $availables)).')';
+            $sql .= ' AND pc.`id_xenforum_cat` IN ('. implode(', ', array_map('intval', $availables)) . ')';
         }
 
         $sql .= ' AND pc.`id_parent` = '.(int)$id_parent.';';
@@ -114,7 +114,7 @@ class XenForumCat extends ObjectModel
             if (empty($availables)) {
                 return false;
             }
-            $sql .= ' AND pc.`id_xenforum_cat` IN ('.pSQL(implode(',', $availables)).')';
+            $sql .= ' AND pc.`id_xenforum_cat` IN ('.implode(', ', array_map('intval', $availables)).')';
         }
 
         $sql .= ' AND pc.`id_parent` = '.(int)$id_parent.'
diff -bpru a/classes/XenForumPost.php b/classes/XenForumPost.php
--- a/classes/XenForumPost.php
+++ b/classes/XenForumPost.php
@@ -161,7 +161,7 @@ class XenForumPost extends ObjectModel
     {
         $sql = 'SELECT * FROM '._DB_PREFIX_.'xenforum_post p
             LEFT JOIN '._DB_PREFIX_.'xenforum x ON (p.id_xenforum = x.id_xenforum)
-            WHERE p.active= 1 AND x.id_xenforum_cat IN ('.pSQL(implode(',', $category_ids)).')';
+            WHERE p.active= 1 AND x.id_xenforum_cat IN ('.implode(', ', array_map('intval', $category_ids)).')';
 
         if (!$posts = Db::getInstance()->executeS($sql)) {
             return 0;
@@ -219,7 +219,7 @@ class XenForumPost extends ObjectModel
             if (empty($availables)) {
                 return false;
             }
-            $sql .= ' AND b.`id_xenforum_cat` IN ('.pSQL(implode(',', $availables)).')';
+            $sql .= ' AND b.`id_xenforum_cat` IN ('.implode(', ', array_map('intval', $availables)).')';
         }
 
         $sql .= ' ORDER BY a.`created` DESC LIMIT '.(int)$limit.';';
diff -bpru a/classes/XenForumTopic.php b/classes/XenForumTopic.php
--- a/classes/XenForumTopic.php
+++ b/classes/XenForumTopic.php
@@ -210,7 +210,7 @@ class XenForumTopic extends ObjectModel
     public function getTotalByCat($category_ids = null)
     {
         $sql = 'SELECT COUNT(id_xenforum) FROM `'._DB_PREFIX_.'xenforum`
-            WHERE `active` = 1 AND `id_xenforum_cat` IN ('.pSQL(implode(',', $category_ids)).')';
+            WHERE `active` = 1 AND `id_xenforum_cat` IN ('.implode(', ', array_map('intval', $category_ids)).')';
 
         return Db::getInstance()->getValue($sql);
     }
@@ -234,7 +234,7 @@ class XenForumTopic extends ObjectModel
             if (empty($availables)) {
                 return false;
             }
-            $sql .= ' AND a.`id_xenforum_cat` IN ('.pSQL(implode(',', $availables)).')';
+            $sql .= ' AND a.`id_xenforum_cat` IN ('.implode(', ', array_map('intval', $availables)).')';
         }
 
         $sql .= ' ORDER BY a.`highlight` DESC, a.`id_xenforum` DESC LIMIT '.(int)$limit_start.', '.(int)$limit;
@@ -264,7 +264,7 @@ class XenForumTopic extends ObjectModel
             if (empty($availables)) {
                 return false;
             }
-            $sql .= ' AND a.`id_xenforum_cat` IN ('.pSQL(implode(',', $availables)).')';
+            $sql .= ' AND a.`id_xenforum_cat` IN ('.implode(', ', array_map('intval', $availables)).')';
         }
 
         $sql .= ' ORDER BY a.`highlight` DESC, a.`id_xenforum` DESC LIMIT '.(int)$limit_start.', '.(int)$limit;
@@ -282,7 +282,7 @@ class XenForumTopic extends ObjectModel
         $sql = 'SELECT a.*, u.* FROM `'._DB_PREFIX_.'xenforum` a
                 LEFT JOIN `'._DB_PREFIX_.'customer` c ON (a.`id_author` = c.`id_customer`)
                 LEFT JOIN '._DB_PREFIX_.'xenforum_user u ON (u.`id_xenforum_user` = c.`id_customer`)
-                WHERE a.`active` = 1 AND c.`active` = 1 AND a.`id_xenforum_cat` IN ('.pSQL(implode(',', $category_ids)).')';
+                WHERE a.`active` = 1 AND c.`active` = 1 AND a.`id_xenforum_cat` IN ('.implode(', ', array_map('intval', $category_ids)).')';
         $sql .= ' ORDER BY a.`id_xenforum` DESC LIMIT 1';
 
         if ($values = Db::getInstance()->executeS($sql)) {
@@ -383,7 +383,7 @@ class XenForumTopic extends ObjectModel
             if (empty($availables)) {
                 return false;
             }
-            $sql .= ' AND a.`id_xenforum_cat` IN ('.pSQL(implode(',', $availables)).')';
+            $sql .= ' AND a.`id_xenforum_cat` IN ('.implode(', ', array_map('intval', $availables)).')';
         }
 
         if (!$posts = Db::getInstance()->executeS($sql)) {

Other recommendations

  • It’s recommended to upgrade the module beyong 2.13.0.
  • To help improve the security of your PrestaShop installation, we recommend upgrading to the latest version. One of the benefits of upgrading is that it will disable the use of multiquery executions (separated by semicolons). However, please be aware that this will not protect your shop against SQL injection attacks that use the UNION clause to steal data. Additionally, it’s important to note that PrestaShop includes a function called pSQL, which includes a strip_tags function. This helps protect your shop against Stored XSS (also known as XSS T2) of Category 1. If a pSQL function is missing, it could potentially expose your project to critical Stored XSS vulnerabilities due to edge cases. Therefore, it’s crucial to ensure that all relevant functions are properly implemented and used consistently throughout your project.
  • Change the default database prefix ps_ by a new longer arbitrary prefix. Nevertheless, be warned that this is useless against blackhats with DBA senior skill because of a design vulnerability in DBMS
  • Activate OWASP 942’s rules on your WAF (Web application firewall), be warned that you will probably break your backoffice and you will need to pre-configure some bypasses against these set of rules.

Timeline

Date Action
2022-10-24 Issue discovered during a code reviews by 202 ecommerce
2022-10-24 Contact the author
2022-11-08 Retry to obtain a response from the author
2022-11-17 Contact PrestaShop Addons Team
2023-01-16 Fix published on addons PrestaShop marketplace
2023-01-28 Request a CVE ID
2023-03-06 Publication of this security advisory