WWBN AVideo is an open-source video platform that includes a wallet plugin (YPTWallet) for managing user balances. In versions up to and including 26.0, the transferBalance() method suffers from a race condition vulnerability classified as CWE-362. The method reads the sender's wallet balance, checks if the balance is sufficient, and then writes the updated balance back to the database. However, this sequence is performed without proper synchronization mechanisms such as database transactions or row-level locking. This creates a Time-of-Check-Time-of-Use (TOCTOU) race condition where multiple concurrent transfer requests from the same authenticated user can simultaneously read the same initial balance before any deductions occur. Each request independently passes the balance sufficiency check, resulting in only one deduction applied to the sender's balance but multiple credits applied to the recipient's balance. This flaw can be exploited by an attacker controlling multiple authenticated sessions to fraudulently increase the recipient's balance without proper deduction from the sender. The vulnerability requires low privileges (authenticated user) and network access but no user interaction. The CVSS 3.1 score is 5.3, reflecting medium severity due to the impact on integrity without affecting confidentiality or availability. The issue was addressed in commit 34132ad5159784bfc7ba0d7634bb5c79b769202d by introducing proper synchronization controls.

The primary impact of this vulnerability is financial fraud through unauthorized balance inflation. Attackers can exploit the race condition to credit multiple times to a recipient's wallet while only deducting once from the sender, causing monetary loss to the sender and potential accounting discrepancies. For organizations relying on WWBN AVideo's wallet system for payments, subscriptions, or internal credits, this can lead to significant financial damage, loss of trust, and reputational harm. Additionally, the integrity of transactional data is compromised, which may affect auditing and compliance. Although the vulnerability does not directly impact confidentiality or availability, the financial and operational consequences can be severe, especially for platforms with high transaction volumes or valuable digital assets. The ease of exploitation is moderate since it requires multiple concurrent authenticated sessions, but no user interaction or elevated privileges. No known exploits are reported in the wild yet, but the vulnerability is publicly disclosed, increasing the risk of future exploitation.

Organizations should immediately upgrade WWBN AVideo to a version that includes the fix (post-commit 34132ad5159784bfc7ba0d7634bb5c79b769202d). If upgrading is not immediately possible, implement the following mitigations: 1) Introduce database-level transactions with appropriate isolation levels to ensure atomicity of balance checks and updates. 2) Employ row-level locking or pessimistic locking on wallet balance records during transfers to prevent concurrent modifications. 3) Implement application-level synchronization mechanisms such as mutexes or semaphores around critical sections handling balance updates. 4) Monitor wallet transactions for anomalies such as multiple concurrent transfers from the same user. 5) Limit the number of concurrent sessions per user or throttle rapid successive transfer requests. 6) Conduct code audits and penetration testing focusing on concurrency and race conditions in financial operations. These measures will reduce the risk of exploitation and ensure transactional integrity.