CVE-2026-63238 in Koollab
Summary
by MITRE • 07/29/2026
An authentication bypass vulnerability in Koollab LMS allowed an unauthenticated attacker to take over any account, including administrator accounts, by supplying a valid user UUID without providing primary credentials via the 2FA validation endpoint.
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Analysis
by VulDB Data Team • 07/29/2026
This vulnerability represents a critical authentication bypass flaw in the Koollab Learning Management System that fundamentally undermines the security model of the platform. The issue stems from improper validation logic within the two-factor authentication endpoint where the system accepts a valid user identifier without requiring proper credential verification. This design flaw creates a pathway for unauthorized access that directly violates established security principles and industry standards such as those outlined in CWE-287 which addresses authentication failures. The vulnerability specifically impacts the authentication flow by allowing attackers to bypass primary authentication mechanisms through the exploitation of a UUID-based access pattern.
The technical implementation of this flaw occurs at the application logic level where the system fails to enforce proper authentication sequence validation. When an attacker supplies a valid user UUID to the 2FA endpoint, the system incorrectly processes the request without requiring standard authentication credentials such as passwords or tokens. This misconfiguration creates a persistent vulnerability that exists across all user accounts including administrative privileges, effectively eliminating the multi-factor authentication protection mechanism. The flaw demonstrates poor input validation and insufficient session management practices that are commonly addressed in security frameworks like OWASP Top Ten and NIST SP 800-53.
The operational impact of this vulnerability is severe and far-reaching within the educational technology ecosystem where Koollab LMS operates. An unauthenticated attacker can execute complete account takeover operations without requiring any valid credentials, password guessing, or other traditional attack vectors. This capability extends to administrative accounts which would provide full system control including user management, content manipulation, and data access. The vulnerability enables persistent threat actor operations that can remain undetected while gaining comprehensive access to sensitive educational data and institutional resources. Such attacks align with techniques documented in the MITRE ATT&CK framework under credential access and privilege escalation domains.
Organizations utilizing Koollab LMS face significant risk exposure including potential data breaches, unauthorized content modification, and complete system compromise. The vulnerability's exploitation requires minimal technical skill and provides maximum impact, making it particularly dangerous for educational institutions that rely on centralized learning management systems. The flaw represents a fundamental failure in the principle of least privilege and proper access control enforcement that should be implemented at every layer of the security architecture. Mitigation strategies must include immediate implementation of proper authentication validation logic, mandatory credential verification before UUID processing, and comprehensive session management controls to prevent similar vulnerabilities from persisting in the system's core functionality.