CVE-2023-51458 is a stored Cross-Site Scripting (XSS) vulnerability identified in Adobe Experience Manager (AEM) versions 6.5.18 and earlier. This vulnerability arises from insufficient input sanitization in certain form fields within the AEM platform, 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 injected script, the malicious code 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 is classified under CWE-79, which covers improper neutralization of input during web page generation. The CVSS v3.1 base score is 5.4 (medium severity), reflecting that the attack vector is network-based, requires low privileges, and user interaction is necessary (the victim must visit the compromised page). The vulnerability impacts confidentiality and integrity but does not affect availability. No known exploits are currently reported in the wild, and no official patches or mitigation links have been provided at the time of publication. Given the widespread use of Adobe Experience Manager in enterprise content management and digital experience delivery, exploitation could facilitate targeted attacks against organizations relying on this platform for web content management.

For European organizations, the impact of this vulnerability can be significant, especially for those using Adobe Experience Manager to manage public-facing websites or intranet portals. Successful exploitation could lead to theft of sensitive user data, including authentication tokens or personal information, potentially violating GDPR requirements on data protection and privacy. It could also enable attackers to perform actions on behalf of users, leading to unauthorized changes or data manipulation within the affected web applications. This may damage organizational reputation, cause regulatory penalties, and disrupt business operations. Since AEM is often used by large enterprises, government agencies, and media companies in Europe, the risk extends to critical sectors such as finance, public administration, and media. The requirement for user interaction (visiting a maliciously crafted page) means social engineering or phishing may be used to lure victims, increasing the risk of targeted spear-phishing campaigns. The medium severity score suggests the threat is moderate but should not be underestimated due to the potential for chained attacks leveraging this vulnerability as an initial foothold.

Organizations should immediately review their Adobe Experience Manager deployments and restrict access to administrative and content management interfaces to trusted users only. Although no official patches are currently available, administrators should implement input validation and output encoding on all user-supplied data within AEM forms to prevent script injection. Employ Content Security Policy (CSP) headers to restrict the execution of unauthorized scripts in browsers. Monitor web application logs for unusual input patterns or repeated form submissions that could indicate exploitation attempts. Educate users about the risks of clicking unknown links or visiting untrusted pages to reduce the likelihood of successful social engineering. Additionally, consider deploying Web Application Firewalls (WAFs) with rules tailored to detect and block XSS payloads targeting AEM. Stay alert for official Adobe security advisories and apply patches promptly once released. Conduct regular security assessments and penetration testing focused on web application vulnerabilities to identify and remediate similar issues proactively.