CVE-2020-9734: XSS in Adobe AEM Forms

The impact of CVE-2020-9734 is significant due to the potential for remote code execution within a user's browser. An attacker could leverage this vulnerability to steal sensitive information, such as session cookies, allowing them to impersonate legitimate users. They could also inject malicious content into the Forms page, redirecting users to phishing sites or delivering malware. Given the 'Author' privilege requirement, the attack would likely target users with elevated permissions within the AEM Forms environment, potentially granting access to broader systems and data. The stored nature of the XSS means the malicious script persists until removed, allowing for repeated exploitation.

1. Reserved2020-03-02
2. Published2020-09-10
3. Modified2024-09-17
4. EPSS updated2026-04-02

As Adobe has not released a fixed version for CVE-2020-9734, mitigation strategies focus on reducing the attack surface and detecting malicious activity. Implement strict input validation and sanitization on all user-supplied data within AEM Forms. Consider restricting 'Author' privileges to only those users who absolutely require them. Employ a Web Application Firewall (WAF) with XSS protection rules to filter out potentially malicious requests. Regularly monitor AEM Forms logs for suspicious activity, such as unusual script injections or unexpected user behavior. While not a direct fix, these measures can significantly reduce the risk of exploitation.