CVE-2026-42698 in Tutor LMS Plugin
Summary
by MITRE • 10/08/2026
Concurrent Execution using Shared Resource with Improper Synchronization ('Race Condition') vulnerability in Themeum Tutor LMS tutor allows Leveraging Race Conditions.This issue affects Tutor LMS: from n/a through 4.1.1.
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Analysis
by VulDB Data Team • 10/08/2026
The identified vulnerability represents a classic race condition within the Themeum Tutor LMS plugin, specifically categorized under CWE-362 as Concurrent Execution using Shared Resource with Improper Synchronization. This flaw arises when multiple threads or processes access shared data structures concurrently without adequate locking mechanisms, leading to unpredictable behavior based on the timing of execution. In the context of web applications like WordPress plugins, this typically manifests during high-concurrency scenarios where asynchronous requests hit critical endpoints simultaneously. The vulnerability affects versions of Tutor LMS from its initial release through version 4.1.1, indicating a systemic lack of synchronization in handling state changes across multiple user interactions or administrative actions.
From a technical perspective, the core issue lies in the failure to implement atomic operations for shared resources such as database records, session variables, or file system states. When two or more requests attempt to modify these resources at nearly the same time, one request may read a value before another has completed its write operation, resulting in data corruption, loss of updates, or unauthorized state transitions. For instance, if a user attempts to enroll in multiple courses simultaneously while an admin is adjusting course limits, the lack of proper synchronization can allow enrollment counts to exceed configured maximums or cause financial discrepancies in paid content access. This type of flaw is particularly dangerous because it is often non-deterministic and difficult to reproduce consistently during standard testing phases, making it a persistent threat vector for attackers who can script rapid-fire requests to exploit the timing window.
The operational impact of this vulnerability extends beyond simple data inconsistency. Attackers leveraging race conditions in LMS platforms can potentially bypass access controls, leading to unauthorized content consumption or privilege escalation. For example, an attacker might manipulate enrollment processes to gain free access to premium courses by exploiting a gap between permission checks and actual database updates. Furthermore, financial integrity is compromised if payment processing logic relies on non-atomic operations, allowing users to circumvent fees or trigger duplicate transactions that result in revenue loss for the institution. In severe cases, race conditions can lead to denial of service through resource exhaustion or cause critical system instability due to corrupted internal states, disrupting educational services and damaging institutional reputation.
Mitigation strategies must focus on enforcing strict synchronization at both the application logic level and the database layer. Developers should replace non-atomic read-modify-write sequences with atomic operations provided by the underlying database engine, such as SELECT FOR UPDATE or optimistic locking mechanisms that check version numbers before committing changes. Implementing distributed locks for critical sections of code ensures that only one process can modify a shared resource at any given time. Additionally, input validation and rate limiting should be applied to endpoints susceptible to concurrent requests to reduce the likelihood of triggering race conditions. Upgrading to patched versions of Tutor LMS beyond 4.1.1 is essential as these releases likely include fixes for synchronization issues identified in earlier builds. Security teams should also conduct thorough code reviews focusing on concurrency patterns and employ static analysis tools capable of detecting potential race condition vulnerabilities during the development lifecycle.
This vulnerability aligns with MITRE ATT&CK technique T1059, Command and Scripting Interpreter, if exploited to execute arbitrary logic through manipulated state changes, or more accurately reflects aspects of privilege escalation via timing attacks. It underscores the importance of secure coding practices in multi-user environments where data integrity is paramount. Organizations relying on Tutor LMS must prioritize immediate patching and implement robust monitoring for anomalous concurrent access patterns that may indicate active exploitation attempts. Continuous integration pipelines should include automated testing scenarios designed to simulate high-concurrency loads, ensuring that synchronization mechanisms function correctly under stress conditions before deployment to production environments.