CVE-2025-47292 is a critical vulnerability classified under CWE-502, which pertains to the deserialization of untrusted data. This vulnerability affects the cap-collectif platform, an online decision-making tool that integrates multiple functionalities to facilitate collaborative processes. The issue resides in the `DebateAlternateArgumentsResolver` component, which deserializes a `Cursor` object. Prior to the fix introduced in commit 812f2a7d271b76deab1175bdaf2be0b8102dd198, this deserialization process allowed any class to be instantiated from user-controlled input without proper validation or restrictions. Since the deserialization occurs without authentication and does not require user interaction, an unauthenticated attacker can craft malicious serialized data to trigger this vulnerability remotely. Exploitation can lead to Remote Code Execution (RCE), enabling attackers to execute arbitrary code on the server hosting the cap-collectif platform. The vulnerability has a CVSS 4.0 base score of 9.5, indicating a critical severity level, with attack vector being network-based, low attack complexity, no privileges required, and no user interaction needed. The impact on confidentiality, integrity, and availability is high, and the scope is changed, meaning the vulnerability can affect components beyond the initially vulnerable module. Although no known exploits are currently reported in the wild, the potential for exploitation is significant given the nature of the vulnerability and the criticality of the affected platform.

For European organizations using cap-collectif, this vulnerability poses a severe risk. Given that cap-collectif is a platform designed for collaborative decision-making, often used by public institutions, NGOs, and private sector entities to facilitate participatory governance and stakeholder engagement, a successful exploit could compromise sensitive decision-making processes and data. Remote Code Execution could allow attackers to manipulate or disrupt ongoing debates, alter stored data, or gain persistent access to internal networks. This could lead to loss of data integrity, unauthorized disclosure of confidential information, and service outages. The impact is particularly critical for organizations involved in public administration, policy-making, or sectors where transparency and data integrity are paramount. Additionally, disruption of such platforms could undermine trust in digital democratic processes. The vulnerability’s exploitation could also serve as a foothold for further lateral movement within affected networks, amplifying the damage.

Organizations should immediately verify their cap-collectif installations and ensure they are updated to at least commit 812f2a7d271b76deab1175bdaf2be0b8102dd198 or later, where the vulnerability is patched. If immediate patching is not feasible, organizations should implement network-level controls to restrict access to the cap-collectif platform, limiting it to trusted IP ranges and enforcing strict firewall rules. Employing Web Application Firewalls (WAFs) with custom rules to detect and block suspicious serialized payloads can provide temporary protection. Additionally, monitoring application logs for unusual deserialization activities or unexpected class instantiations can help detect exploitation attempts. Organizations should also conduct thorough security audits of their deployment environments to identify any signs of compromise. Finally, adopting secure coding practices that avoid deserialization of untrusted data or implementing strict allowlists for deserializable classes can prevent similar vulnerabilities in the future.