CVE-2026-85038 in B2BKing Plugin
Summary
by MITRE • 09/06/2026
The B2BKing — Ultimate WooCommerce B2B and Wholesale Plugin — Wholesale Prices, Bulk Order Form & More WordPress plugin before 5.2.40 does not verify that a role selected during registration is one actually offered on the registration form, allowing unauthenticated users to assign themselves to restricted B2B customer groups and to skip the manual account-approval workflow during self-registration.
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Analysis
by VulDB Data Team • 09/06/2026
The vulnerability identified in versions of the B2BKing — Ultimate WooCommerce B2B and Wholesale Plugin prior to 5.2.40 represents a critical failure in access control logic, specifically categorized under CWE-862 Missing Authorization. This flaw arises from an insufficient validation mechanism during the user registration process within WordPress environments that utilize this plugin for business-to-business commerce operations. The core technical deficiency lies in the application's inability to verify whether the role selected by a new registrant corresponds to one of the roles explicitly enabled and offered on the public-facing registration form. Instead of enforcing server-side constraints based on configured allowed roles, the system accepts any role string submitted during the registration request, provided it exists within the WordPress database schema. This lack of strict input validation allows an attacker or malicious actor to manipulate the HTTP POST data associated with account creation, injecting a user role that is intended for internal staff, administrators, or specific high-tier wholesale partners rather than standard customers.
The operational impact of this vulnerability is severe due to its unauthenticated nature and direct implications for business logic integrity. By exploiting this flaw, an attacker can bypass the manual account approval workflow typically enforced by B2B plugins to ensure that new vendors or buyers meet certain criteria before gaining access. This results in unauthorized privilege escalation where a user gains elevated permissions without proper vetting. In many B2B configurations, specific roles are tied to restricted pricing tiers, bulk order capabilities, and exclusive product visibility. Consequently, an attacker can register as a wholesale partner with full privileges, potentially accessing confidential pricing structures, placing orders at discounted rates intended for verified partners, or even gaining administrative access if the misconfigured role maps to higher-level permissions within the WordPress ecosystem. This undermines the fundamental security model of the B2B platform, which relies on controlled onboarding processes to maintain commercial integrity and data confidentiality.
From a threat modeling perspective, this vulnerability aligns with MITRE ATT&CK technique T1078 Valid Accounts, as it involves the creation or use of legitimate-looking credentials that possess unauthorized privileges due to configuration flaws rather than credential theft. It also relates to CWE-269 Improvement of Privileges through improper handling of external inputs during account provisioning. The absence of server-side role validation means that client-side restrictions are easily bypassed using standard web request manipulation tools, making this vulnerability highly exploitable by automated scripts or low-skill attackers. The impact extends beyond simple unauthorized access; it can lead to significant financial loss through fraudulent bulk ordering at wholesale prices and potential data breaches if the elevated roles allow access to sensitive customer information or order histories that should be restricted to verified business entities only.
Mitigation strategies must focus on immediate patching and robust server-side validation implementation. The primary remediation is to upgrade the B2BKing plugin to version 5.2.40 or later, where this logic error has been addressed by enforcing strict role whitelisting during registration. For organizations unable to update immediately due to compatibility constraints with other plugins, a temporary workaround involves implementing custom code hooks in WordPress functions.php that intercept the user registration process and forcibly override any submitted role data against a hardcoded list of allowed roles defined by the site administrator. Additionally, security teams should review existing user accounts for anomalies, checking for newly created users who possess elevated privileges without corresponding approval records. Long-term architectural improvements should include implementing strict input validation frameworks across all WordPress plugins to ensure that no external input influences critical access control decisions without rigorous server-side verification against a predefined set of authorized values.