CVE-2025-13239 identifies a security vulnerability in the Bdtask Isshue Multi Store eCommerce Shopping Cart Solution version 5, specifically within the /submit_checkout functionality. The vulnerability arises from improper handling and validation of the order_total_amount and cart_total_amount parameters, which can be manipulated by an attacker to enforce unintended behavioral workflows during the checkout process. This manipulation could allow an attacker to alter the expected transaction flow, potentially bypassing business logic controls or causing inconsistent order states. The attack vector is remote and does not require user interaction or authentication, increasing the risk of exploitation. The CVSS 4.0 base score of 5.3 reflects a medium severity, with characteristics including network attack vector, low attack complexity, no privileges or user interaction required, and limited impact on integrity. The vendor was notified early but has not issued a patch or response, and no known public exploits have been reported yet. The vulnerability could be leveraged to disrupt eCommerce operations, cause financial discrepancies, or facilitate fraud by manipulating checkout amounts. Given the critical role of the checkout process in eCommerce, this vulnerability poses a tangible risk to affected installations.

For European organizations using the Bdtask Isshue Multi Store eCommerce Shopping Cart Solution, this vulnerability could lead to unauthorized manipulation of transaction amounts during checkout, potentially resulting in financial losses, order processing errors, or fraudulent transactions. Disruption of the checkout workflow may degrade customer trust and damage brand reputation. Since the exploit requires no authentication and can be launched remotely, attackers could automate exploitation at scale, impacting availability and integrity of eCommerce services. The lack of vendor response and absence of patches increases the window of exposure. European eCommerce businesses, especially those handling high volumes of transactions, may face operational and financial risks. Additionally, regulatory compliance concerns such as GDPR may arise if transaction data integrity is compromised, leading to potential legal and financial penalties.

In absence of an official patch, European organizations should implement strict input validation and sanitization on the /submit_checkout endpoint, particularly for order_total_amount and cart_total_amount parameters, to ensure values conform to expected formats and ranges. Employ web application firewalls (WAFs) with custom rules to detect and block anomalous parameter manipulations related to checkout amounts. Monitor transaction logs for irregularities or discrepancies between cart totals and submitted order amounts. Implement anomaly detection systems to flag unusual checkout workflows or repeated failed attempts. Consider deploying rate limiting on checkout submissions to reduce automated exploitation risk. Engage in threat hunting for signs of exploitation attempts. If possible, isolate or restrict access to the vulnerable component until a vendor patch or update is available. Maintain up-to-date backups of transaction data to enable recovery from potential disruptions. Finally, liaise with Bdtask or community forums for any emerging patches or mitigation guidance.