CVE-2023-48516 is a stored Cross-Site Scripting (XSS) vulnerability identified in Adobe Experience Manager (AEM) versions 6.5.18 and earlier. This vulnerability allows a low-privileged attacker to inject malicious JavaScript code into vulnerable form fields within the AEM environment. When a victim subsequently accesses the affected page containing the injected script, the malicious code executes in their browser context. Stored XSS vulnerabilities are particularly dangerous because the malicious payload is saved on the server and delivered to multiple users, increasing the attack surface and potential impact. The vulnerability requires low privileges to exploit, but user interaction is necessary as the victim must visit the compromised page. The CVSS v3.1 base score is 5.4 (medium severity), reflecting network attack vector, low attack complexity, low privileges required, and user interaction needed. The impact affects confidentiality and integrity by potentially stealing session tokens, performing actions on behalf of the user, or defacing content, but does not affect availability. No known exploits are currently reported in the wild, and no official patches have been linked yet. The vulnerability is classified under CWE-79, which covers improper neutralization of input leading to XSS attacks.

For European organizations using Adobe Experience Manager, this vulnerability poses a moderate risk. AEM is widely used by enterprises and public sector organizations across Europe for content management and digital experience delivery. Exploitation could lead to unauthorized access to sensitive information, session hijacking, or unauthorized actions performed in the context of legitimate users, potentially including administrators. This could result in data breaches, reputational damage, and compliance violations under GDPR if personal data is exposed. Public sector entities and large enterprises with high web traffic are particularly at risk due to the potential scale of impact. The requirement for user interaction limits automated exploitation but targeted phishing or social engineering campaigns could increase risk. Since no patches are currently linked, organizations must rely on interim mitigations to reduce exposure. The medium severity score suggests that while the threat is significant, it is not critical, but should be addressed promptly to prevent escalation or chaining with other vulnerabilities.

1. Implement strict input validation and output encoding on all form fields in AEM to prevent injection of malicious scripts. 2. Use Content Security Policy (CSP) headers to restrict the execution of unauthorized scripts in browsers accessing AEM content. 3. Limit user privileges and enforce the principle of least privilege to reduce the ability of low-privileged users to inject malicious content. 4. Monitor web application logs and user activity for unusual input patterns or script injections. 5. Educate users and administrators about the risks of clicking on suspicious links or content within AEM-managed sites. 6. Apply any forthcoming official patches from Adobe promptly once available. 7. Consider deploying Web Application Firewalls (WAF) with rules to detect and block XSS payloads targeting AEM. 8. Regularly review and update AEM configurations and custom code to adhere to secure coding practices and prevent similar vulnerabilities.