CVE-2023-48548 is a stored Cross-Site Scripting (XSS) vulnerability affecting Adobe Experience Manager (AEM) versions 6.5.18 and earlier. This vulnerability arises from insufficient input sanitization in certain form fields, allowing a low-privileged attacker to inject malicious JavaScript code that is persistently stored on the server. When a victim user accesses the affected page containing the malicious payload, the injected script executes in their browser context. This can lead to unauthorized actions such as session hijacking, credential theft, or performing actions on behalf of the user. The vulnerability requires low privileges to exploit but does require user interaction (the victim must visit the compromised page). The CVSS 3.1 base score is 5.4 (medium severity), reflecting network attack vector, low attack complexity, low privileges required, user interaction needed, and partial impact on confidentiality and integrity but no impact on availability. The vulnerability is significant because AEM is widely used by enterprises and public sector organizations for managing web content and digital assets, making it a valuable target for attackers seeking to compromise user sessions or deface websites. No known exploits in the wild have been reported yet, and no official patches are linked in the provided data, indicating that organizations should prioritize mitigation and monitoring until a patch is available.

For European organizations, the impact of this vulnerability could be substantial, especially for those relying on Adobe Experience Manager to manage public-facing websites or intranet portals. Exploitation could lead to theft of user credentials, unauthorized access to sensitive information, or manipulation of web content, potentially damaging brand reputation and violating data protection regulations such as GDPR. The partial compromise of confidentiality and integrity could expose personal data or internal communications. Since AEM is often used by government agencies, financial institutions, and large enterprises in Europe, successful exploitation could disrupt critical services or lead to regulatory penalties. The requirement for user interaction means phishing or social engineering could be used to lure victims to vulnerable pages, increasing risk in environments with high user traffic. Although availability is not impacted, the reputational and compliance consequences could be severe.

European organizations should implement the following specific mitigations: 1) Immediately audit all AEM instances to identify versions at or below 6.5.18 and prioritize upgrading to the latest patched version once available. 2) In the absence of a patch, apply strict input validation and output encoding on all form fields to prevent script injection, potentially using web application firewalls (WAFs) with custom rules targeting suspicious payloads. 3) Conduct thorough security testing and code reviews focusing on user input handling in AEM components. 4) Educate users and administrators about the risks of clicking on untrusted links and the importance of reporting suspicious website behavior. 5) Monitor web server logs and application logs for unusual input patterns or repeated attempts to inject scripts. 6) Implement Content Security Policy (CSP) headers to restrict execution of unauthorized scripts in browsers. 7) Limit privileges of users who can submit content to minimize the attack surface. These measures, combined with timely patching, will reduce the risk of exploitation.