CVE-2025-24575 in HelloAsso Plugin
Summary
by MITRE • 01/24/2025
Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting') vulnerability in HelloAsso HelloAsso allows Stored XSS. This issue affects HelloAsso: from n/a through 1.1.11.
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Analysis
by VulDB Data Team • 02/09/2025
The vulnerability identified as CVE-2025-24575 represents a critical cross-site scripting flaw within the HelloAsso web application platform that enables attackers to execute malicious scripts in the context of authenticated users. This stored XSS vulnerability specifically impacts versions of HelloAsso ranging from an unspecified initial version through 1.1.11, creating a significant security risk for organizations relying on this platform for their web applications and services. The flaw occurs during the web page generation process where input validation and sanitization mechanisms fail to properly neutralize malicious user-supplied data before rendering it in web pages.
The technical implementation of this vulnerability stems from inadequate input processing within the HelloAsso application's web rendering pipeline. When users submit content or parameters that are subsequently displayed on web pages without proper sanitization, attackers can inject malicious script code that persists in the application's database or storage mechanisms. This stored nature of the vulnerability means that the malicious payload remains active and executes every time the affected page is loaded or accessed by any user, including administrators. The vulnerability aligns with CWE-79 which specifically addresses cross-site scripting flaws in web applications, where the weakness allows attackers to inject client-side scripts into web pages viewed by other users.
The operational impact of this vulnerability extends beyond simple data theft or session hijacking. An attacker exploiting this stored XSS flaw could potentially escalate privileges, gain administrative access, or manipulate critical application functionality through the execution of malicious scripts. The vulnerability's persistence means that even if the initial injection occurs during a brief window, the malicious code continues to execute for all subsequent users who access the affected pages, creating a prolonged attack surface. This particular vulnerability affects the core web application functionality of HelloAsso, potentially compromising user data, session information, and overall platform integrity.
Security professionals should consider this vulnerability in the context of the MITRE ATT&CK framework, specifically under the T1566 technique for credential access through social engineering and T1059 for command and control through scripting. The stored nature of the XSS attack allows for more sophisticated exploitation patterns where attackers can create persistent backdoors or data exfiltration mechanisms. Organizations utilizing HelloAsso versions within the affected range should immediately implement defensive measures including input validation, output encoding, and content security policies to mitigate the risk. The vulnerability requires immediate attention as it represents a fundamental flaw in the application's security architecture that could enable comprehensive compromise of the platform's user base and associated data.