CVE-2026-14325 in Drag and Drop Multiple File Upload for Contact Form 7 Plugin
Summary
by MITRE • 08/21/2026
The Drag and Drop Multiple File Upload for Contact Form 7 WordPress plugin before 1.3.9.9 does not escape one of its settings before using it as an HTML tag name in front-end output, allowing users with administrator access to inject arbitrary web scripts that execute on any front-end page rendering its upload field.
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Analysis
by VulDB Data Team • 08/21/2026
The vulnerability identified in the Drag and Drop Multiple File Upload for Contact Form 7 WordPress plugin prior to version 1.3.9.9 represents a critical stored cross-site scripting flaw rooted in improper input validation and output encoding mechanisms. The core technical deficiency lies within the plugin's handling of configuration settings, specifically those related to file upload fields. When an administrator configures these settings through the backend interface, the application fails to properly sanitize or escape specific values before incorporating them into HTML markup that is subsequently rendered on public-facing pages. This lack of sanitization allows for the injection of arbitrary JavaScript code directly into the DOM structure during page rendering operations. The flaw exploits a classic input validation failure where trusted administrative inputs are treated as safe without sufficient verification against malicious payloads, leading to unintended execution contexts within the browser environment of end-users visiting sites that utilize this plugin.
From an operational perspective, this vulnerability poses significant risks to both website administrators and their visitors. Since the injection occurs via administrator-level access, it requires a higher privilege level than typical unauthenticated attacks but remains highly dangerous due to its persistent nature. Once injected, the malicious script executes every time a front-end page containing the affected upload field is loaded by any visitor. This persistence means that even if the initial administrative session ends or credentials are compromised and changed later, the payload remains active until manually removed from the plugin settings. The impact extends beyond simple defacement; attackers can leverage this execution context to steal session cookies, hijack user sessions, perform actions on behalf of victims such as modifying contact form submissions, or redirect users to phishing sites designed to harvest credentials. This effectively turns a standard file upload feature into a vector for widespread client-side attacks against the site's audience.
In terms of industry classification standards, this vulnerability aligns closely with CWE-79, which describes Improper Neutralization of Input During Web Page Generation commonly known as Cross-site Scripting (XSS). Specifically, it falls under stored XSS variants where malicious content is saved on target servers and later served to other users. Furthermore, the exploitation technique maps directly to MITRE ATT&CK tactic TA0001, Initial Access, specifically through techniques like Valid Accounts or Spearphishing Attachment if an attacker gains administrative access via credential theft. The attack vector also relates to execution phases where scripts are run in a browser context without user interaction beyond page load, fitting into the Execution category under client-side code injection patterns. Understanding these mappings helps security teams prioritize remediation efforts based on established threat intelligence frameworks and common vulnerability enumeration guidelines.
Mitigation strategies must focus primarily on immediate patching and rigorous input validation practices. The most effective solution is to upgrade the Drag and Drop Multiple File Upload for Contact Form 7 plugin to version 1.3.9.9 or later, where developers have addressed this specific encoding oversight by implementing proper HTML entity escaping functions before rendering settings as tag names. For organizations unable to patch immediately due to compatibility constraints, temporary workarounds include restricting administrative access through multi-factor authentication and IP whitelisting to reduce the risk of credential compromise leading to exploitation. Additionally, deploying a Web Application Firewall with rules capable of detecting and blocking reflected or stored XSS payloads can provide an additional layer of defense by intercepting malicious scripts before they execute in user browsers. Regular security audits focusing on output encoding practices across all plugins are essential to prevent similar vulnerabilities from emerging in the future, ensuring that no administrative input is ever rendered directly into HTML structures without appropriate sanitization checks.