CVE-2024-21504 in livewire
Summary
by MITRE • 03/19/2024
Versions of the package livewire/livewire from 3.3.5 and before 3.4.9 are vulnerable to Cross-site Scripting (XSS) when a page uses [Url] for a property. An attacker can inject HTML code in the context of the user's browser session by crafting a malicious link and convincing the user to click on it.
Once again VulDB remains the best source for vulnerability data.
Analysis
by VulDB Data Team • 08/26/2025
The vulnerability identified as CVE-2024-21504 affects the livewire/livewire package, specifically versions between 3.3.5 and 3.4.8 inclusive, presenting a critical cross-site scripting vulnerability that can compromise user sessions and enable malicious code execution. This vulnerability manifests when applications utilize the [Url] directive for property binding within Livewire components, creating a pathway for attackers to inject malicious HTML content that executes in the context of legitimate user sessions. The flaw resides in the insufficient sanitization of URL parameters that are processed through the Livewire framework's property binding mechanism, allowing crafted malicious links to bypass security controls and inject arbitrary script code into web pages. The vulnerability operates under CWE-79 which categorizes cross-site scripting flaws as weaknesses in input validation and output encoding, specifically targeting the failure to properly escape or sanitize user-provided data before rendering it within web page contexts. This issue aligns with ATT&CK technique T1531 which involves techniques for executing malicious code through web-based attacks, particularly emphasizing the exploitation of web application vulnerabilities to gain unauthorized access to user sessions. The security implications extend beyond simple script injection as attackers can leverage this vulnerability to steal session cookies, perform unauthorized actions on behalf of users, or redirect victims to malicious domains. The vulnerability's exploitation requires social engineering to convince users to click on crafted malicious links, but once triggered, it can compromise the integrity of user sessions and potentially lead to full account takeovers or data exfiltration.
The technical exploitation of this vulnerability occurs when a Livewire component processes a URL parameter through the [Url] directive without proper sanitization of the input. When users navigate to a maliciously crafted URL that contains script tags or other malicious payloads within the URL parameters, these inputs are processed by Livewire's property binding system and rendered directly into the page without appropriate HTML escaping or context-aware sanitization. This creates a persistent XSS vector where the malicious code executes in the victim's browser context with the privileges of the authenticated user. The vulnerability is particularly dangerous because Livewire applications often handle sensitive user data and may perform privileged operations, making the potential impact of a successful XSS attack significantly more severe. The attack surface is expanded by the fact that many web applications use URL parameters for various purposes including navigation, configuration, or data passing, providing multiple potential entry points for exploitation. The vulnerability affects applications where developers rely on Livewire's automatic property binding for URL parameters, particularly in scenarios where user-supplied URLs are processed through the framework's component lifecycle.
The operational impact of CVE-2024-21504 extends beyond immediate code execution capabilities to encompass broader security implications for web applications utilizing the Livewire framework. Organizations running affected versions face potential data breaches, session hijacking, and unauthorized access to user accounts, particularly in applications that handle sensitive information or perform administrative functions. The vulnerability can be exploited to create persistent backdoors within applications, allowing attackers to maintain access over extended periods. Security teams must consider the potential for cascading effects where a successful XSS attack could lead to further compromise of application infrastructure or user data. The vulnerability's presence in widely used packages increases the attack surface across numerous applications and organizations, making it a high-priority issue for security operations teams. Additionally, the vulnerability affects not just individual applications but entire ecosystems of software that depend on Livewire, potentially requiring coordinated patching efforts across multiple systems. The impact is further compounded by the fact that XSS vulnerabilities often go undetected for extended periods, allowing attackers to establish persistent footholds within networks.
Organizations should immediately upgrade to Livewire version 3.4.9 or later to remediate this vulnerability, as this represents the first patched release that addresses the insufficient sanitization of URL parameters in the [Url] directive. Security teams should implement comprehensive monitoring for suspicious URL patterns and user behavior that might indicate exploitation attempts, particularly focusing on unusual navigation patterns or unexpected script execution. Network-level defenses should include web application firewalls that can detect and block malicious URL patterns associated with known XSS payloads. Development teams should conduct thorough code reviews focusing on property binding patterns and ensure all user-supplied URL parameters undergo proper sanitization before processing. The remediation process should include a comprehensive audit of all Livewire components that utilize URL parameter binding to identify potential exposure points. Security controls should be implemented to enforce proper input validation and output encoding for all URL parameters, particularly those processed through Livewire's automatic property binding mechanisms. Organizations should also consider implementing content security policies that restrict script execution and limit the potential impact of successful XSS attacks, though these should complement rather than replace proper input sanitization. The vulnerability highlights the importance of maintaining up-to-date dependencies and implementing robust security testing procedures that include vulnerability scanning for commonly used web frameworks and libraries.