CVE-2025-64821 is a stored Cross-Site Scripting (XSS) vulnerability identified in Adobe Experience Manager (AEM) versions 6.5.23 and earlier. Stored XSS occurs when malicious scripts are permanently stored on a target server, such as within form fields, and later executed in the browsers of users who access the affected content. In this case, a low-privileged attacker can submit malicious JavaScript code into vulnerable form fields within AEM. When other users browse pages containing these fields, the injected scripts execute in their browsers, potentially allowing theft of session cookies, user impersonation, or manipulation of displayed content. The vulnerability requires the attacker to have some level of access to submit data but does not require administrative privileges. User interaction is necessary as victims must visit the compromised page. The CVSS 3.1 score of 5.4 reflects a medium severity, with network attack vector, low attack complexity, low privileges required, and user interaction needed. The scope is changed, indicating the vulnerability can affect components beyond the initially vulnerable module. No public exploits are known at this time, but the risk remains significant due to the widespread use of AEM in enterprise web content management. The vulnerability is classified under CWE-79, which covers improper neutralization of input leading to XSS. Since no patch links are currently available, organizations must rely on interim mitigations.

For European organizations, the impact of this vulnerability can be substantial, especially for those relying on Adobe Experience Manager for critical web content delivery, such as government portals, financial institutions, and media companies. Successful exploitation could lead to unauthorized disclosure of sensitive information, including session tokens and personal data, undermining user trust and violating data protection regulations like GDPR. Integrity of web content could be compromised, enabling attackers to inject misleading or malicious content, potentially damaging reputation and causing operational disruptions. Although availability is not directly impacted, the indirect effects of compromised user sessions and trust can be severe. The medium severity rating suggests moderate risk, but the widespread deployment of AEM in Europe increases the potential attack surface. Organizations that do not promptly address this vulnerability may face targeted phishing campaigns or broader exploitation attempts once public exploits emerge.

1. Monitor Adobe’s official channels for patches addressing CVE-2025-64821 and apply them immediately upon release. 2. Implement strict input validation on all form fields to reject or sanitize potentially malicious scripts before storage. 3. Employ comprehensive output encoding to ensure that any user-supplied data rendered in web pages cannot execute as code. 4. Configure Content Security Policy (CSP) headers to restrict the execution of inline scripts and loading of untrusted resources, reducing the impact of injected scripts. 5. Conduct regular security audits and penetration testing focused on XSS vulnerabilities within AEM deployments. 6. Educate content managers and users about the risks of interacting with suspicious links or content. 7. Use web application firewalls (WAFs) with rules tuned to detect and block common XSS attack patterns targeting AEM. 8. Limit privileges for users who can submit content to the minimum necessary to reduce the risk of malicious input injection.