CVE-2025-64557 is a stored Cross-Site Scripting (XSS) vulnerability identified in Adobe Experience Manager (AEM) versions 6.5.23 and earlier. The vulnerability arises from insufficient sanitization of user-supplied input in certain form fields, allowing an attacker with low privileges to inject malicious JavaScript code that is persistently stored on the server. When other users access the affected pages containing the injected scripts, the malicious code executes in their browsers, potentially leading to session hijacking, credential theft, or unauthorized actions performed on behalf of the victim. The vulnerability is classified under CWE-79, indicating improper neutralization of input during web page generation. The CVSS 3.1 base score is 5.4, reflecting a medium severity level, with attack vector network (AV:N), low attack complexity (AC:L), requiring privileges (PR:L), and user interaction (UI:R). The scope is changed (S:C), meaning the vulnerability can affect resources beyond the initially vulnerable component. Confidentiality and integrity impacts are low, while availability is not affected. No public exploits are known at this time, but the vulnerability's presence in a widely used enterprise content management system makes it a notable risk. Adobe has not yet released patches, so organizations must rely on interim mitigations.

For European organizations, the impact of CVE-2025-64557 can be significant, especially for those relying on Adobe Experience Manager for web content delivery and digital services. Exploitation could lead to unauthorized disclosure of sensitive information such as session cookies or personal data, undermining user trust and potentially violating GDPR requirements. Attackers could also manipulate web content, leading to misinformation or phishing attacks targeting employees or customers. The medium severity rating indicates moderate risk, but the changed scope means that exploitation could affect multiple users or systems beyond the initial vulnerability point. Organizations in sectors with high regulatory scrutiny, such as finance, healthcare, and government, face increased reputational and compliance risks. Additionally, the need for user interaction and privileges limits exploitation but does not eliminate risk, especially in environments with many users or where privilege escalation is possible.

To mitigate CVE-2025-64557, European organizations should: 1) Monitor Adobe's security advisories closely and apply official patches immediately upon release. 2) Implement strict input validation and output encoding on all form fields within AEM to prevent malicious script injection. 3) Deploy Content Security Policy (CSP) headers to restrict the execution of unauthorized scripts in browsers. 4) Limit user privileges within AEM to the minimum necessary, reducing the risk of low-privileged attackers exploiting the vulnerability. 5) Conduct regular security audits and penetration testing focused on web application vulnerabilities. 6) Educate users about the risks of interacting with suspicious content to reduce the likelihood of successful exploitation. 7) Consider using web application firewalls (WAFs) with rules designed to detect and block XSS payloads targeting AEM. 8) Review and harden session management mechanisms to prevent session hijacking in case of XSS exploitation.