CVE-2025-64863 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 target servers, 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 inject malicious JavaScript code into vulnerable form fields in AEM. When legitimate users browse pages containing these fields, the injected scripts execute within their browser context, potentially allowing the attacker to steal session cookies, perform actions on behalf of the user, or redirect users to malicious sites. The vulnerability is exploitable remotely over the network (AV:N), requires low attack complexity (AC:L), and only low privileges (PR:L) but does require user interaction (UI:R). The scope is changed (S:C), indicating that the vulnerability affects resources beyond the initially vulnerable component. The impact affects confidentiality and integrity (C:L/I:L) but not availability (A:N). Despite the medium CVSS score of 5.4, the vulnerability poses a significant risk to organizations relying on AEM for web content delivery, especially those with public-facing portals where attackers can lure users to vulnerable pages. No known exploits have been reported in the wild yet, and no official patches have been linked, indicating the need for proactive mitigation. The vulnerability is tracked under CWE-79, a common and well-understood class of web application security issues.

For European organizations, this vulnerability can lead to unauthorized disclosure of sensitive information such as session tokens, user credentials, or personal data through malicious script execution. Attackers could leverage this to impersonate users, escalate privileges, or conduct further attacks such as phishing or malware distribution. Organizations using AEM for public-facing websites or intranet portals are particularly at risk, as attackers can inject scripts that affect a broad user base. This can result in reputational damage, regulatory non-compliance (e.g., GDPR violations due to data leakage), and potential financial losses. The medium severity score reflects moderate impact, but the widespread use of AEM in Europe and the potential for chained attacks elevate the risk. The requirement for user interaction means social engineering or phishing may be used to exploit the vulnerability, increasing the attack surface. Additionally, the scope change indicates that the vulnerability could affect multiple components or users beyond the initial entry point, amplifying potential damage.

1. Implement strict server-side input validation and sanitization on all form fields within Adobe Experience Manager to prevent injection of malicious scripts. 2. Deploy and enforce Content Security Policy (CSP) headers to restrict execution of unauthorized scripts and reduce the impact of XSS attacks. 3. Regularly audit and monitor web application logs and user inputs for suspicious or anomalous activity indicative of script injection attempts. 4. Isolate critical user sessions and implement HttpOnly and Secure flags on cookies to reduce the risk of session hijacking. 5. Educate users about phishing and social engineering tactics to reduce the likelihood of successful exploitation requiring user interaction. 6. Apply any available security updates or patches from Adobe promptly once released. 7. Consider using web application firewalls (WAFs) with rules specifically designed to detect and block XSS payloads targeting AEM. 8. Conduct regular security assessments and penetration testing focused on XSS vulnerabilities in AEM deployments. 9. Limit the privileges of users who can submit content to the system to reduce the risk of malicious input. 10. Review and harden AEM configurations to minimize exposed attack surfaces and disable unnecessary features that could be exploited.