CVE-2025-64555 is a stored Cross-Site Scripting (XSS) vulnerability identified in Adobe Experience Manager (AEM) versions 6.5.23 and earlier. This vulnerability arises from insufficient sanitization of user input in certain form fields, allowing a low-privileged attacker to inject malicious JavaScript code that is stored persistently on the server. When other users access the affected pages containing these vulnerable fields, the malicious script executes within their browsers, potentially leading to session hijacking, credential theft, or unauthorized actions performed on behalf of the victim. The vulnerability requires the attacker to have some level of privilege to submit data but does not require administrative rights. User interaction is necessary for the exploit to succeed, as victims must visit the compromised page. The CVSS 3.1 base score of 5.4 reflects a medium severity, with an attack vector over the network (AV:N), low attack complexity (AC:L), requiring privileges (PR:L), user interaction (UI:R), and impacting confidentiality and integrity with a scope change (S:C). No public exploits have been reported yet, but the vulnerability poses a significant risk to organizations relying on AEM for web content management, especially where sensitive data or user sessions are involved. The lack of a patch at the time of reporting necessitates immediate mitigation efforts to reduce exposure.

For European organizations, this vulnerability can lead to unauthorized disclosure of sensitive information, including user credentials and session tokens, through malicious script execution in users' browsers. This can result in compromised user accounts, unauthorized access to internal systems, and potential data breaches. Since AEM is widely used for managing digital content and customer-facing websites, exploitation could damage organizational reputation and trust, especially under stringent European data protection regulations like GDPR. The vulnerability does not directly affect system availability but undermines data integrity and confidentiality. Attackers could leverage this to conduct phishing campaigns, spread malware, or pivot to further internal attacks. Organizations with high web traffic and customer interaction are at greater risk, as more users could be exposed to malicious scripts. The medium severity rating suggests a moderate but non-negligible risk that requires timely remediation to prevent escalation.

European organizations should implement several targeted mitigation strategies beyond generic advice: 1) Immediately audit all AEM instances to identify vulnerable versions and affected form fields. 2) Apply strict input validation and sanitization on all user-submitted data, especially in forms exposed to low-privileged users. 3) Employ output encoding techniques to neutralize any injected scripts before rendering content in browsers. 4) Restrict the ability of low-privileged users to submit potentially dangerous content or scripts. 5) Monitor web traffic and logs for unusual input patterns or script injections indicative of exploitation attempts. 6) Educate web developers and administrators on secure coding practices specific to AEM and XSS prevention. 7) Prepare to deploy official Adobe patches promptly once released, and consider temporary workarounds such as disabling vulnerable features or applying web application firewall (WAF) rules to block suspicious payloads. 8) Conduct regular security testing, including automated scanning and manual penetration testing focused on XSS vulnerabilities in AEM environments.