CVE-2025-46866 is a stored Cross-Site Scripting (XSS) vulnerability affecting Adobe Experience Manager (AEM) versions 6.5.22 and earlier. This vulnerability arises from insufficient input sanitization in certain form fields within AEM, allowing a low-privileged attacker to inject malicious JavaScript code that is persistently stored on the server. When a victim subsequently accesses the affected page containing the vulnerable form field, the malicious script executes in their browser context. This DOM-based XSS flaw (CWE-79) can lead to unauthorized actions such as session hijacking, defacement, or redirection to malicious sites. The vulnerability has a CVSS 3.1 base score of 5.4, indicating a medium severity level. It requires network access, low attack complexity, and low privileges but does require user interaction (the victim visiting the compromised page). The scope is changed (S:C), meaning the vulnerability affects components beyond the initially vulnerable component, potentially impacting confidentiality and integrity but not availability. No known exploits are currently reported in the wild, and no patches have been linked yet. Given AEM's role as a content management system widely used for enterprise web portals, this vulnerability could be leveraged to compromise user trust and data confidentiality.

For European organizations, the impact of this vulnerability can be significant, especially for those relying on Adobe Experience Manager for public-facing websites, intranets, or customer portals. Exploitation could lead to theft of session tokens, enabling attackers to impersonate users or administrators, potentially exposing sensitive personal data protected under GDPR. It could also facilitate phishing attacks by injecting malicious content into trusted web pages, damaging brand reputation and customer trust. While availability is not directly impacted, the integrity and confidentiality of user interactions and data are at risk. Organizations in sectors such as finance, healthcare, government, and e-commerce, which often use AEM for content delivery, may face regulatory and compliance repercussions if exploited. The requirement for user interaction means that social engineering or targeted campaigns could increase the likelihood of successful exploitation.

To mitigate this vulnerability, European organizations should prioritize upgrading Adobe Experience Manager to the latest version once Adobe releases an official patch addressing CVE-2025-46866. In the interim, organizations should implement strict input validation and output encoding on all form fields within AEM to prevent injection of malicious scripts. Employ Content Security Policy (CSP) headers to restrict the execution of unauthorized scripts and reduce the impact of any injected code. Regularly audit and monitor web application logs for unusual input patterns or script injections. Educate users about the risks of clicking unknown links and visiting suspicious pages. Additionally, consider deploying web application firewalls (WAFs) with custom rules to detect and block XSS payloads targeting AEM. Finally, conduct thorough security testing, including automated and manual penetration tests focusing on XSS vectors in AEM environments.