CVE-2025-64620 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 input is saved on the server and later rendered in a victim's browser without proper sanitization. In this case, a low-privileged attacker can inject malicious JavaScript code into vulnerable form fields within AEM. When other users access the affected pages, the injected scripts execute in their browsers, potentially allowing the attacker to steal session cookies, perform actions on behalf of the user, or manipulate page content. The vulnerability has a CVSS 3.1 base score of 5.4, indicating medium severity. The attack vector is network-based (AV:N), with low attack complexity (AC:L), requiring low privileges (PR:L) and user interaction (UI:R). The scope is changed (S:C), meaning the vulnerability affects resources beyond the initially vulnerable component. The impacts include partial confidentiality and integrity loss (C:L/I:L) but no availability impact (A:N). No public exploits are known at this time, but the vulnerability poses a risk to organizations using AEM for web content management, especially those exposing forms to external users. The lack of available patches at the time of reporting necessitates immediate mitigation through configuration and monitoring. The vulnerability stems from improper input validation and output encoding in form fields, a common cause of stored XSS. Attackers exploiting this flaw can compromise user sessions and potentially escalate privileges or move laterally within affected environments.

For European organizations, the impact of CVE-2025-64620 can be significant, particularly for those relying on Adobe Experience Manager to deliver web content and manage customer interactions. Exploitation could lead to theft of sensitive user data such as authentication tokens, enabling session hijacking and unauthorized access to protected resources. This can result in data breaches, reputational damage, and regulatory penalties under GDPR due to exposure of personal data. Additionally, attackers could manipulate website content to conduct phishing or distribute malware, further harming users and the organization. The medium severity score reflects that while the vulnerability requires some user interaction and low privileges, the scope change and confidentiality/integrity impacts can facilitate broader compromise if chained with other vulnerabilities. Public-facing AEM deployments in sectors like finance, government, healthcare, and e-commerce are particularly at risk, as attackers may target these for high-value data or disruption. The absence of known exploits currently reduces immediate risk but does not eliminate the threat, especially as attackers often develop exploits quickly after disclosure. Organizations failing to mitigate this vulnerability may face increased risk of targeted attacks and compliance violations.

To mitigate CVE-2025-64620 effectively, European organizations should: 1) Monitor Adobe's official channels closely and apply security patches or updates as soon as they become available for AEM versions 6.5.23 and earlier. 2) Implement strict input validation on all form fields to reject or sanitize potentially malicious scripts before storage. 3) Employ robust output encoding/escaping mechanisms when rendering user-supplied data in web pages to prevent script execution. 4) Deploy Content Security Policy (CSP) headers to restrict the execution of unauthorized scripts and reduce the impact of XSS attacks. 5) Conduct regular security audits and penetration testing focused on web application vulnerabilities, including stored XSS. 6) Use web application firewalls (WAFs) with updated rules to detect and block malicious payloads targeting known AEM vulnerabilities. 7) Educate developers and administrators on secure coding practices and the risks of XSS. 8) Monitor logs and user behavior for anomalies that may indicate exploitation attempts. 9) Consider isolating or restricting access to vulnerable AEM instances until patches are applied. These measures, combined, reduce the attack surface and limit the potential damage from exploitation.