CVE-2026-0679 identifies a missing authorization vulnerability (CWE-862) in the Fortis for WooCommerce plugin for WordPress, specifically in versions up to and including 1.2.0. The vulnerability stems from an inverted nonce check within the 'check_fortis_notify_response' function, which is intended to verify the authenticity of incoming notifications related to payment status updates. Due to this flawed logic, the nonce validation can be bypassed, allowing unauthenticated remote attackers to send crafted requests that update arbitrary WooCommerce order statuses to 'paid', 'processing', or 'completed' without any legitimate payment transaction. This bypass does not require any user authentication or interaction, making it trivially exploitable over the network. The impact is primarily on the integrity of order data, enabling attackers to fraudulently mark orders as paid, potentially causing financial loss and operational disruption. The vulnerability has a CVSS v3.1 base score of 5.3 (medium severity), reflecting its ease of exploitation and impact on data integrity without affecting confidentiality or availability. No patches or known exploits have been reported at the time of publication, but the risk remains significant for e-commerce sites relying on this plugin for payment processing.

For European organizations operating e-commerce platforms using WooCommerce with the Fortis payment plugin, this vulnerability poses a direct threat to financial integrity and operational reliability. Attackers can fraudulently mark orders as paid, leading to unauthorized order fulfillment, inventory depletion, and financial losses. This can also damage customer trust and result in reputational harm. Since the vulnerability requires no authentication or user interaction, it can be exploited by any remote attacker, increasing the attack surface. The integrity of order processing workflows is compromised, potentially affecting accounting and reconciliation processes. Organizations may face increased chargebacks and disputes from customers. The impact is particularly critical for high-volume e-commerce businesses and those with limited fraud detection capabilities. Additionally, regulatory compliance risks may arise if fraudulent transactions are not promptly detected and mitigated.

1. Monitor for updates from Fortis for WooCommerce and apply patches immediately once available. 2. Until patches are released, implement server-side validation to verify payment status updates against trusted payment gateway notifications, ensuring that order status changes correspond to legitimate transactions. 3. Restrict access to the 'check_fortis_notify_response' endpoint by IP whitelisting or firewall rules to only allow known payment gateway IPs. 4. Enable detailed logging and monitoring of order status changes to detect suspicious or unauthorized modifications promptly. 5. Employ anomaly detection mechanisms to flag sudden or unusual order status updates, especially those marking orders as paid without corresponding payment records. 6. Educate operational teams to review orders marked as paid for unusual patterns and verify payment confirmations manually if necessary. 7. Consider implementing multi-factor verification for critical order status changes in the WooCommerce backend. 8. Regularly audit WooCommerce plugin versions and configurations to ensure no vulnerable versions remain in production.