CVE-2025-64539: Adobe Experience Manager XSS Vulnerability

CVE-2025-64539 Overview

Adobe Experience Manager versions 6.5.23 and earlier are affected by a DOM-based Cross-Site Scripting (XSS) vulnerability that could lead to arbitrary code execution. An attacker could exploit this vulnerability by injecting malicious scripts into a web page that are executed in the context of the victim's browser. A successful attacker can abuse this to achieve session takeover, significantly increasing the confidentiality and integrity impact. Exploitation of this issue requires user interaction in that a victim must visit a crafted malicious page.

Critical Impact

This DOM-based XSS vulnerability enables attackers to execute arbitrary code in victim browsers, potentially leading to complete session takeover and unauthorized access to sensitive Adobe Experience Manager content and administrative functions.

Affected Products

• Adobe Experience Manager versions 6.5.23 and earlier
• Adobe Experience Manager AEM Cloud Service (affected versions)
• Adobe Experience Manager 6.5 LTS

Discovery Timeline

• 2025-12-10 - CVE-2025-64539 published to NVD
• 2025-12-12 - Last updated in NVD database

Technical Details for CVE-2025-64539

Vulnerability Analysis

This vulnerability is classified as CWE-79 (Improper Neutralization of Input During Web Page Generation), specifically manifesting as a DOM-based Cross-Site Scripting (XSS) attack. The vulnerability allows attackers to inject malicious scripts that execute within the context of a victim's browser session when they visit a specially crafted page.

The attack requires no authentication or elevated privileges, making it accessible to unauthenticated remote attackers. However, user interaction is required—the victim must be tricked into visiting a malicious page or clicking a crafted link. Due to the changed scope characteristic, successful exploitation can impact resources beyond the vulnerable component itself.

The primary impact of this vulnerability is on confidentiality and integrity, both rated as high. Session takeover enables attackers to impersonate legitimate users, access sensitive content management data, and potentially modify published content on sites managed by Adobe Experience Manager.

Root Cause

The vulnerability stems from improper handling of user-controlled input within the Document Object Model (DOM) of Adobe Experience Manager. When untrusted data is processed by client-side JavaScript without adequate sanitization or encoding, it creates an injection point for malicious scripts. DOM-based XSS differs from traditional reflected or stored XSS in that the payload is executed entirely on the client side through DOM manipulation, without being processed by the server.

Attack Vector

The attack is network-based, requiring an attacker to craft a malicious URL or webpage containing the XSS payload. The attacker must then convince a victim to visit this malicious resource through social engineering techniques such as phishing emails, malicious advertisements, or compromised websites. Once the victim's browser processes the malicious page, the injected script executes with the same privileges as the legitimate Adobe Experience Manager application, enabling session hijacking, credential theft, or further malicious actions.

The exploitation mechanism relies on DOM manipulation techniques where attacker-controlled input flows into dangerous DOM sinks (such as innerHTML, document.write, or eval) without proper sanitization. See the Adobe Security Advisory APSB25-115 for additional technical details on affected components.

Detection Methods for CVE-2025-64539

Indicators of Compromise

• Unusual JavaScript execution patterns in Adobe Experience Manager pages, particularly involving DOM manipulation functions
• Web application firewall logs showing attempted XSS payloads targeting AEM endpoints
• Browser console errors or unexpected script execution on AEM-hosted pages
• Authentication session anomalies or unexpected privilege escalation events

Detection Strategies

• Implement Content Security Policy (CSP) headers and monitor for policy violations that may indicate XSS attempts
• Deploy web application firewalls with signatures for common XSS attack patterns targeting AEM
• Enable detailed logging on Adobe Experience Manager instances to capture suspicious request patterns
• Monitor for unusual client-side DOM manipulation activity through browser-based security tools

Monitoring Recommendations

• Review web server access logs for requests containing encoded script tags or JavaScript event handlers
• Implement real-time alerting on suspicious user session behavior that may indicate session hijacking
• Monitor authentication events for anomalies following potential exposure to malicious content
• Track Content Security Policy violation reports to identify attempted XSS exploitation

How to Mitigate CVE-2025-64539

Immediate Actions Required

• Apply the security update referenced in Adobe Security Advisory APSB25-115 immediately
• Review and strengthen Content Security Policy headers on all AEM deployments
• Educate users about the risks of clicking untrusted links, particularly those targeting AEM resources
• Implement additional input validation and output encoding at the application layer where possible

Patch Information

Adobe has released security updates to address this vulnerability. Administrators should apply the patches documented in Adobe Security Advisory APSB25-115. Organizations running Adobe Experience Manager versions 6.5.23 or earlier should prioritize upgrading to the latest patched version. For AEM Cloud Service deployments, ensure automatic updates are enabled and verify the latest security patches have been applied.

Workarounds

• Implement strict Content Security Policy headers to limit script execution sources and reduce XSS impact
• Deploy a Web Application Firewall (WAF) configured with XSS detection rules specific to AEM endpoints
• Restrict access to Adobe Experience Manager interfaces to trusted networks where feasible
• Enable HTTP-only and Secure flags on session cookies to limit session hijacking impact

# Example Content Security Policy header configuration for Apache
# Add to httpd.conf or .htaccess for AEM deployments
Header set Content-Security-Policy "default-src 'self'; script-src 'self'; object-src 'none'; frame-ancestors 'self';"
Header set X-Content-Type-Options "nosniff"
Header set X-XSS-Protection "1; mode=block"