CVE-2026-75713: Adobe Experience Manager XSS Vulnerability

CVE-2026-75713 Overview

Adobe Experience Manager (AEM) contains a DOM-based Cross-Site Scripting (XSS) vulnerability tracked as CVE-2026-75713. An attacker can manipulate the Document Object Model (DOM) environment to execute arbitrary JavaScript in the victim's browser session. Exploitation requires user interaction: the victim must visit a crafted webpage while authenticated with low privileges. The vulnerability has a changed scope, meaning executed script can affect resources beyond the vulnerable component. The issue is classified under [CWE-79] Improper Neutralization of Input During Web Page Generation.

Critical Impact
Successful exploitation allows attackers to run JavaScript in the authenticated victim's browser context, enabling session token theft, unauthorized actions inside AEM, and content manipulation across trust boundaries.

Affected Products

Adobe Experience Manager Cloud Service (AEM as a Cloud Service)
Adobe Experience Manager 6.5 LTS (base release)
Adobe Experience Manager 6.5 LTS Service Pack 1 and Service Pack 2

Discovery Timeline

2026-09-08 - CVE-2026-75713 published to the National Vulnerability Database
2026-09-10 - Last updated in NVD database

Technical Details for CVE-2026-75713

Vulnerability Analysis

The flaw is a client-side DOM-based XSS issue within Adobe Experience Manager. Client-side JavaScript in AEM writes attacker-controlled data into a DOM sink without proper neutralization. When the victim loads a crafted URL or page that references the vulnerable component, the browser parses the injected payload as executable script.

Because the scope is changed, script execution in the victim's session can influence resources outside the vulnerable component's original security context. This includes access to cookies, DOM data, and any AEM administrative surface reachable through the victim's session. Confidentiality and integrity impacts are limited but tangible, while availability is unaffected.

Root Cause

The root cause is missing sanitization or encoding of untrusted input before it reaches a DOM sink such as innerHTML, document.write, or a similar JavaScript API. AEM client-side code trusts data supplied through URL fragments, query parameters, or other browser-controlled sources. Adobe's advisory APSB26-98 documents the affected components and fixed versions.

Attack Vector

Exploitation is network-based and requires both low-privileged authentication and user interaction. The attacker crafts a malicious URL or page that manipulates DOM state consumed by AEM client scripts. The victim, typically an authenticated AEM author or administrator, visits the page and triggers script execution. The injected JavaScript then acts under the victim's AEM session, potentially performing content modifications, exfiltrating session data, or pivoting to other AEM interfaces.

No public proof-of-concept exploit is available at the time of publication, and the vulnerability is not listed in the CISA Known Exploited Vulnerabilities catalog.

Detection Methods for CVE-2026-75713

Indicators of Compromise

Unusual outbound requests from AEM author or publish instances following authenticated user browsing sessions.
AEM audit log entries showing content changes or configuration updates originating from legitimate accounts but tied to unexpected referrer URLs.
Web server logs containing requests with encoded JavaScript payloads in URL fragments, query strings, or hash parameters targeting AEM endpoints.

Detection Strategies

Deploy Content Security Policy (CSP) reporting to capture blocked inline script executions in AEM author interfaces.
Inspect HTTP request logs for URLs containing characters commonly used in DOM XSS payloads such as <script, javascript:, onerror=, and onload=.
Correlate AEM session activity with browser referrer data to identify sessions redirected from untrusted external origins before privileged actions.

Monitoring Recommendations

Enable verbose logging on AEM dispatcher and reverse proxy layers to preserve full request URIs including fragments where feasible.
Monitor privileged AEM accounts for anomalous content edits, package installations, or user privilege modifications.
Alert on browser-side CSP violation reports referencing AEM author domains.

How to Mitigate CVE-2026-75713

Immediate Actions Required

Apply Adobe's security update referenced in advisory APSB26-98 to all AEM Cloud Service and AEM 6.5 LTS deployments.
Restrict access to AEM author instances to trusted networks and require multi-factor authentication for all privileged accounts.
Train content authors and administrators to avoid clicking links from untrusted sources while authenticated to AEM.

Patch Information

Adobe released fixes covering AEM Cloud Service and AEM 6.5 LTS Service Pack releases. Refer to Adobe Security Advisory APSB26-98 for the exact fixed build numbers and upgrade instructions. Customers on AEM as a Cloud Service receive updates automatically through Adobe's release channel, while on-premises AEM 6.5 LTS operators must schedule the patch deployment.

Workarounds

Enforce a strict Content Security Policy on AEM author domains to block inline script execution and restrict script sources.
Deploy a Web Application Firewall rule set that filters common DOM XSS payload patterns targeting AEM URLs.
Segment AEM author interfaces onto isolated administrative networks accessible only through a VPN or zero trust broker.

bash

# Example CSP header for AEM author dispatcher configuration
Header set Content-Security-Policy "default-src 'self'; \
  script-src 'self'; \
  object-src 'none'; \
  base-uri 'self'; \
  frame-ancestors 'self'; \
  report-uri /csp-report"