CVE-2026-63240 in Koollab LMS
Summary
by MITRE • 07/29/2026
An information disclosure vulnerability in Koollab LMS allowed an authenticated learner to obtain correct quiz answers from the course status endpoint without completing the assessment legitimately, compromising the integrity of assessments.
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Analysis
by VulDB Data Team • 07/29/2026
This vulnerability represents a critical information disclosure flaw in the Koollab Learning Management System that undermines the fundamental integrity of online assessment processes. The issue manifests through an improperly secured course status endpoint that fails to validate whether learners have legitimately completed assessments before providing access to correct quiz answers. This weakness allows authenticated users to bypass normal assessment completion requirements and directly retrieve answer data, effectively nullifying the purpose of quizzes and exams within the learning platform.
The technical implementation of this vulnerability stems from inadequate access control mechanisms within the course status endpoint. When an authenticated learner makes a request to this endpoint, the system does not perform proper authentication checks or verify that the user has completed the assessment process before returning sensitive answer information. This misconfiguration creates an unauthorized data exposure scenario where learners can obtain correct answers without fulfilling the required assessment completion criteria. The vulnerability aligns with CWE-200, which addresses improper information disclosure, and specifically demonstrates weaknesses in access control validation mechanisms.
The operational impact of this vulnerability extends far beyond simple data exposure, fundamentally compromising the assessment integrity that educational institutions rely upon for measuring learner progress and competency. When learners can obtain correct answers without completing assessments, it creates an environment where academic dishonesty becomes trivially achievable, undermining the credibility of course completion records and potentially invalidating certification programs built on these platforms. This vulnerability directly affects the trustworthiness of learning outcomes and could lead to serious consequences for both educational institutions and individual learners who depend on verified competency assessments.
Organizations utilizing Koollab LMS should implement immediate mitigations including strengthening access controls on all assessment-related endpoints, implementing proper authentication checks before returning answer data, and establishing audit trails for assessment access requests. The solution requires enforcing that users must complete assessment processes before gaining access to correct answers, utilizing proper session management, and implementing rate limiting to prevent automated exploitation attempts. Additionally, this vulnerability highlights the importance of conducting regular security assessments of LMS platforms and implementing proper input validation and output encoding practices to prevent similar information disclosure scenarios from occurring in other endpoints or applications.
The incident demonstrates how seemingly minor access control oversights can create significant security implications within educational technology platforms, particularly those handling sensitive assessment data. This type of vulnerability commonly appears in web applications where authentication and authorization logic is not consistently applied across all API endpoints, making it a prime example of the need for comprehensive security testing throughout the software development lifecycle. Organizations should consider implementing automated security scanning tools and regular penetration testing to identify similar access control weaknesses before they can be exploited by malicious actors. The vulnerability also underscores the importance of following secure coding practices such as those outlined in the OWASP Top Ten project, particularly focusing on access control and information disclosure prevention measures that are critical for maintaining assessment integrity in digital learning environments.