CVE-2026-63241 in Koollab
Summary
by MITRE • 07/29/2026
An insecure direct object reference vulnerability in Koollab LMS allowed an authenticated user to query the course completion progress of any other user without authorisation, disclosing private learning progress information.
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Analysis
by VulDB Data Team • 07/29/2026
This vulnerability represents a critical access control flaw that undermines the security model of Koollab LMS by enabling unauthorized data disclosure through insecure direct object reference mechanisms. The weakness manifests when authenticated users can manipulate object references to access course completion progress data belonging to other users without proper authorization. This type of vulnerability falls under CWE-639 which specifically addresses Insecure Direct Object Reference issues where applications fail to verify that the user has proper authorization to access requested resources. The flaw operates at the application logic level where the system directly uses user-supplied input as a reference to access internal objects without appropriate validation or authorization checks.
The operational impact of this vulnerability extends beyond simple information disclosure, creating potential privacy violations and undermining user trust in the learning management system. An authenticated attacker can exploit this weakness to query any user's course completion status, potentially revealing sensitive academic information that could be used for social engineering attacks or competitive advantage. The vulnerability is particularly concerning in educational environments where student privacy and academic progress data are considered sensitive information requiring proper access controls. This flaw directly violates the principle of least privilege and demonstrates a failure in implementing proper authorization mechanisms within the application's resource access controls.
From an attack perspective, this vulnerability aligns with techniques described in the MITRE ATT&CK framework under the privilege escalation and credential access domains where attackers can leverage existing authenticated sessions to bypass authorization controls. The exploitation process requires minimal technical skill as it relies on predictable object references or parameter manipulation that allows enumeration of user resources. Security professionals should note that this vulnerability often occurs when developers assume that authentication is sufficient protection, failing to implement proper authorization checks for each resource access request. The attack surface expands significantly when considering that authenticated users may have elevated privileges within the system but still lack proper boundaries for accessing other users' data.
The recommended mitigations involve implementing robust access control mechanisms that validate user permissions before granting access to any resource. This includes using indirect object references with server-side mapping tables, implementing proper authorization checks at each access point, and ensuring that all user requests are validated against the authenticated user's permissions. Organizations should also consider implementing audit logging for sensitive data access patterns and regular security testing to identify similar vulnerabilities. The solution must address the root cause by establishing proper authorization controls rather than merely patching specific instances of the vulnerability, ensuring that the system maintains consistent access control policies across all user interactions with course progress data.