CVE-2026-96338 in Profile Builder Plugin
Summary
by MITRE • 09/30/2026
Subscriber Cross Site Scripting (XSS) in Profile Builder <= 4.0.2 versions.
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Analysis
by VulDB Data Team • 09/30/2026
The vulnerability identified as Subscriber Cross-Site Scripting within the Profile Builder plugin for WordPress, affecting versions up to and including 4.0.2, represents a significant security flaw that compromises user data integrity through client-side code injection. This specific type of cross-site scripting is categorized under CWE-79, which denotes Improper Neutralization of Input During Web Page Generation. Unlike administrative XSS vulnerabilities that require high-level privileges, this vulnerability targets subscribers and lower-tier users, allowing any authenticated individual with a subscriber role to execute malicious scripts in the context of other users' browsers. The root cause lies in insufficient input validation and output encoding mechanisms within the profile editing functionality or related user metadata fields managed by the plugin. When a victim subscribes to a site or updates their profile information, specific inputs are stored without adequate sanitization against script tags or event handlers.
From an operational perspective, this flaw enables attackers to perform session hijacking attacks where they can steal authentication cookies and tokens associated with other users on the same domain. By crafting a malicious payload that exploits the lack of encoding in displayed user profiles or public-facing member lists, an attacker can trick a victim into loading a page containing their script. Once executed within the victim's browser context, the injected code has access to all privileged actions available to that role, potentially leading to unauthorized account manipulation, defacement of site content if higher privileges are escalated through social engineering, or redirection to phishing sites designed to capture further credentials. This aligns with MITRE ATT&CK technique T1059, specifically sub-technique 007 for JavaScript execution, which is commonly used in web-based attacks to bypass traditional network security controls that do not inspect client-side behavior.
The impact extends beyond simple cookie theft as it undermines the trust model of multi-user WordPress installations where community interaction and user-generated content are central features. Attackers can leverage this vulnerability to conduct persistent campaigns against specific targets by embedding tracking pixels or keyloggers within profile fields that are rendered publicly. Because the flaw exists in a widely used plugin, the attack surface is broad, affecting numerous websites across various industries that rely on membership functionality. The lack of immediate neutralization means that any user with access to edit their own public-facing information can propagate this risk to others viewing those profiles, creating a chain reaction effect where one compromised account or malicious actor can impact multiple victims simultaneously without requiring server-side exploitation.
Mitigation strategies must prioritize immediate patching as the primary defense vector. Administrators should upgrade Profile Builder to version 4.0.3 or later, which includes patches for input sanitization and output encoding issues that resolve this specific XSS flaw. In environments where upgrading is not immediately feasible due to compatibility constraints with other plugins or custom code modifications, temporary mitigations involve implementing strict Content Security Policy headers that restrict script execution sources and disable inline scripts using the nonce attribute or hash-based restrictions. Additionally, deploying a Web Application Firewall can help filter out malicious payloads attempting to inject script tags into user profile fields before they reach the application logic. Regular security audits focusing on how user inputs are rendered in public-facing templates will further reduce the risk of similar vulnerabilities emerging from other plugins or core themes that may share similar architectural patterns for handling subscriber data.