CVE-2025-31455 in Limit Max IPs per User Plugin
Summary
by MITRE • 04/02/2025
Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting') vulnerability in NotFound Limit Max IPs Per User allows DOM-Based XSS. This issue affects Limit Max IPs Per User: from n/a through 1.5.
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Analysis
by VulDB Data Team • 04/02/2025
This vulnerability represents a critical cross-site scripting flaw that specifically targets the Limit Max IPs Per User plugin version 1.5 and earlier. The issue manifests as a DOM-based XSS vulnerability, which means that malicious input is processed and executed within the browser's Document Object Model rather than being reflected from the server response. The vulnerability occurs during the web page generation process when user input is not properly sanitized or neutralized before being incorporated into dynamic web content. This particular implementation flaw allows attackers to inject malicious scripts that can execute in the context of the victim's browser session, potentially leading to unauthorized actions or data theft. The vulnerability affects all versions from the initial release through version 1.5, indicating a long-standing issue that has not been adequately addressed in the plugin's input handling mechanisms.
The technical exploitation of this vulnerability relies on the plugin's failure to properly validate and sanitize user-supplied data that gets rendered into web pages. When users interact with the plugin's interface or submit data through forms, the input validation mechanisms are insufficient to prevent malicious script injection. This allows an attacker to craft malicious payloads that can be stored or transmitted through the plugin's functionality, ultimately executing within the victim's browser context. The DOM-based nature of the vulnerability means that the attack vector operates entirely within the browser environment, making it particularly challenging to detect and mitigate through traditional server-side security measures. The vulnerability stems from inadequate input sanitization during the page generation phase, where user data is directly incorporated into DOM elements without proper escaping or encoding.
The operational impact of this vulnerability extends beyond simple script execution, potentially enabling sophisticated attack scenarios that can compromise user sessions and access sensitive information. Attackers can leverage this vulnerability to hijack user sessions, steal cookies, perform unauthorized actions on behalf of victims, or redirect users to malicious websites. The vulnerability's presence in the plugin's core functionality means that any user interacting with the affected system could become a victim of the XSS attack. The implications are particularly severe for environments where the plugin is used to manage IP address restrictions, as attackers could potentially manipulate the system's behavior or access restricted functionality. This type of vulnerability can also serve as a stepping stone for more complex attacks, potentially leading to privilege escalation or complete system compromise depending on the broader environment.
Security mitigations for this vulnerability should focus on implementing comprehensive input validation and output encoding mechanisms throughout the plugin's codebase. The recommended approach involves applying proper HTML escaping and JavaScript encoding to all user-supplied data before rendering it in web pages. Additionally, implementing Content Security Policy headers can provide an additional layer of protection against XSS attacks by restricting script execution. The plugin developers should also consider implementing proper input sanitization routines and validating all user inputs against strict whitelists of acceptable characters. This vulnerability aligns with CWE-79 which specifically addresses cross-site scripting flaws, and the ATT&CK framework's T1059.007 technique for script injection. Organizations should immediately update to the latest version of the plugin once available and conduct thorough security assessments of their web applications to identify similar vulnerabilities in other components that may be susceptible to DOM-based XSS attacks.