Ameeba Security Research

Defensive CVE and exploit intelligence

Ameeba Blog Search
TRENDING · 1 WEEK
Attack Vector
Vendor
Severity

CVE-2025-59833: Unauthorized Access to Challenge Hints in Flag Forge CTF Platform

Views: 13

Overview

CVE-2025-59833 is a security vulnerability found in the Flag Forge Capture The Flag (CTF) platform, which leaves challenge hints exposed in plaintext. This flaw affects versions 2.1.0 to 2.2.9 and can be exploited by any user without requiring point deductions, disrupting the business logic of the platform and potentially impacting the integrity of the challenge system.

Vulnerability Summary

CVE ID: CVE-2025-59833
Severity: High (7.5 CVSS score)
Attack Vector: Network
Privileges Required: None
User Interaction: None
Impact: Undermined integrity of the challenge system, potential system compromise, and data leakage.

Affected Products

Ameeba Chat Icon Share secrets securely

Ameeba is private infrastructure for communication and sensitive work built on encrypted identity instead of exposed corporate identity systems.

Passwords, credentials, confidential files, screenshots, internal discussions, sensitive AI context, and private coordination should not become exposed across ordinary communication platforms.

  • • Encrypted identity
  • • Private Spaces for organizations and teams
  • • End-to-end encrypted chat, calls, files, and notes
  • • Sensitive AI work and protected collaboration
  • • Built for information that cannot leak

Our mission is to secure human work alongside AI.

Product | Affected Versions

Flag Forge | 2.1.0 to 2.2.9

How the Exploit Works

The exploit takes advantage of the API endpoint GET /api/problems/:id. This endpoint is improperly configured to return challenge hints in plaintext within the question object, regardless of whether the user has unlocked them via point deduction. This means that any user can view all hints for free, without the necessary point deductions, thus bypassing the intended mechanism.

Conceptual Example Code

The vulnerability might be exploited using a simple HTTP request such as the following:

GET /api/problems/123 HTTP/1.1
Host: target.example.com

In this example, “123” is the id of a specific challenge. The server would then respond with the challenge data, including the hints in plaintext, regardless of the user’s actual point status.

Mitigation

A patch for this issue has been released in version 2.3.0 of the Flag Forge platform. Users are strongly recommended to update to this version or later. In cases where immediate patching is not possible, using a Web Application Firewall (WAF) or Intrusion Detection System (IDS) can offer temporary mitigation. These systems should be configured to monitor and block suspicious activity at the affected API endpoint.

Want to discuss this further? Join the Ameeba Cybersecurity Group Chat.

Disclaimer:

The information and code presented in this article are provided for educational and defensive cybersecurity purposes only. Any conceptual or pseudocode examples are simplified representations intended to raise awareness and promote secure development and system configuration practices.

Do not use this information to attempt unauthorized access or exploit vulnerabilities on systems that you do not own or have explicit permission to test.

Ameeba and its authors do not endorse or condone malicious behavior and are not responsible for misuse of the content. Always follow ethical hacking guidelines, responsible disclosure practices, and local laws.

More posts

Ameeba Chat