CVE-2025-46878 is a stored Cross-Site Scripting (XSS) vulnerability affecting Adobe Experience Manager (AEM) versions 6.5.22 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 maliciously crafted form field, the injected script executes in their browser context. This can lead to a range of malicious outcomes including session hijacking, unauthorized actions performed on behalf of the user, theft of sensitive information, or delivery of further malware payloads. The vulnerability requires the attacker to have low-level privileges to submit the malicious input but does not require elevated privileges. User interaction is necessary as the victim must visit the compromised page for the script to execute. The CVSS 3.1 base score is 5.4, reflecting a medium severity level, with the vector indicating network attack vector (AV:N), low attack complexity (AC:L), low privileges required (PR:L), user interaction required (UI:R), scope changed (S:C), and impacts on confidentiality and integrity but not availability (C:L/I:L/A:N). No known exploits are currently reported in the wild, and no official patches or mitigation links have been provided at this time. The vulnerability is categorized under CWE-79, which is a common and well-understood web application security issue related to improper neutralization of input leading to script injection.

For European organizations using Adobe Experience Manager, this vulnerability poses a moderate risk primarily to the confidentiality and integrity of web application data and user sessions. Exploitation could allow attackers to impersonate legitimate users, steal authentication tokens, or manipulate content displayed to users, potentially damaging organizational reputation and leading to data breaches. Given AEM's widespread use in managing digital content and customer-facing portals, compromised sites could be leveraged for phishing campaigns or to distribute malware to European users. The impact is heightened in sectors with stringent data protection requirements such as finance, healthcare, and government, where unauthorized data disclosure or manipulation could lead to regulatory penalties under GDPR. Additionally, the scope change indicated by the CVSS vector suggests that exploitation could affect resources beyond the initially vulnerable component, increasing the potential damage. However, the requirement for user interaction and low privileges limits the ease of exploitation compared to more critical vulnerabilities.

European organizations should prioritize the following mitigation steps: 1) Immediate review and sanitization of all user input fields within Adobe Experience Manager forms to ensure proper encoding and validation against script injection. 2) Implement Content Security Policy (CSP) headers to restrict the execution of unauthorized scripts in browsers, limiting the impact of any injected code. 3) Conduct thorough security testing and code reviews focusing on input handling in AEM instances, especially for custom components or extensions. 4) Monitor web application logs and user reports for suspicious activity indicative of XSS exploitation attempts. 5) Educate users and administrators about the risks of clicking on untrusted links or submitting unverified content. 6) Stay alert for official Adobe patches or security advisories and apply updates promptly once available. 7) Consider deploying Web Application Firewalls (WAFs) with rules tailored to detect and block XSS payloads targeting AEM. These measures go beyond generic advice by focusing on proactive input validation, layered defense, and organizational awareness specific to the AEM environment.