CVE-2026-79410 in Bagisto
Summary
by MITRE • 09/15/2026
Improper validation of the quantity parameter in the add-to-cart path of Webkul Bagisto v2.4.9 allows authenticated attackers to reduce their order total below the legitimate price of shippable goods.
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Analysis
by VulDB Data Team • 09/15/2026
The vulnerability identified in Webkul Bagisto version 2.4.9 represents a critical business logic flaw rooted in improper input validation within the e-commerce transaction processing pipeline. Specifically, the defect resides in the add-to-cart functionality where the system fails to adequately verify or constrain the quantity parameter submitted by authenticated users during checkout operations. In standard secure implementations, backend systems must enforce strict boundaries on numerical inputs to ensure that they align with available inventory and do not violate pricing integrity rules. However, in this instance, the application accepts negative integers or excessively large quantities without applying necessary server-side validation checks against predefined minimum thresholds or logical constraints associated with product availability and cost calculations.
This lack of rigorous parameter sanitization allows an authenticated attacker to manipulate the order total by inputting a quantity value that effectively reduces the final price below the legitimate market value of the shippable goods. By exploiting this logic error, an adversary can potentially acquire products for free or at a significantly discounted rate by manipulating the mathematical calculation performed on the server side. The core technical failure is not necessarily in the encryption or network transmission but rather in the application's internal business rules enforcement mechanism, which trusts client-supplied data without sufficient verification against expected operational limits.
The operational impact of this vulnerability extends beyond simple financial loss to include broader implications for inventory management and system integrity. When an attacker successfully exploits this flaw, it results in direct revenue erosion as orders are processed at incorrect prices. Furthermore, if the quantity manipulation allows for negative stock levels or bypasses inventory reservation logic, it can lead to data inconsistency where physical stock does not match digital records. This discrepancy complicates supply chain operations and may result in order fulfillment failures when actual inventory is insufficient to cover manipulated requests. Additionally, such exploits undermine customer trust and brand reputation if discovered publicly, as they indicate a fundamental weakness in the platform's security posture regarding transactional integrity.
From a classification perspective, this vulnerability aligns with CWE-20 Improper Input Validation, specifically where the application fails to validate that input data meets expected constraints before processing. It also relates closely to CWE-840 Performing Business Logic on Untrusted Inputs, as the system performs critical financial calculations based on user-controlled parameters without adequate safeguards. In terms of offensive security frameworks, this exploit maps to MITRE ATT&CK technique T1567 Exploit Public-Facing Application, leveraging a flaw in an internet-facing service for unauthorized economic gain. The attack vector is classified as local or adjacent depending on authentication requirements but typically involves remote exploitation by authenticated users who have access to the checkout interface.
Mitigation strategies must focus on implementing robust server-side validation logic that enforces strict boundaries on all numerical inputs related to financial transactions. Developers should ensure that quantity parameters are validated against minimum and maximum limits defined in the database schema or business rules engine before any price calculations occur. It is essential to implement positive integer checks, ensuring that quantities cannot be negative or zero unless explicitly allowed by specific product configurations. Additionally, employing idempotency keys for checkout requests can help prevent replay attacks where an attacker might attempt to exploit race conditions alongside this logic flaw. Regular security audits and penetration testing focused on business logic vulnerabilities are recommended to identify similar weaknesses in other parts of the e-commerce platform before they can be exploited by malicious actors.