CVE-2026-75636: Adobe Experience Manager XSS Vulnerability

CVE-2026-75636 Overview

Adobe Experience Manager (AEM) contains a DOM-based Cross-Site Scripting (XSS) vulnerability tracked as CVE-2026-75636. An attacker can manipulate the Document Object Model (DOM) environment to execute arbitrary JavaScript in the victim's browser context. Exploitation requires user interaction because the victim must visit a crafted webpage. The scope is changed, meaning the impact extends beyond the vulnerable component to other resources. The flaw is categorized as [CWE-79] Improper Neutralization of Input During Web Page Generation. Adobe published Security Advisory APSB26-98 addressing this issue.

Critical Impact
Successful exploitation allows attackers to run malicious JavaScript in the victim's browser session, potentially leading to session data theft, unauthorized actions, and phishing pivots against AEM users.

Affected Products

Adobe Experience Manager (see Adobe Security Advisory APSB26-98 for affected versions)

Discovery Timeline

2026-09-08 - CVE CVE-2026-75636 published to NVD
2026-09-09 - Last updated in NVD database

Technical Details for CVE-2026-75636

Vulnerability Analysis

The vulnerability is a client-side DOM-based XSS flaw in Adobe Experience Manager. Unlike reflected or stored XSS, DOM-based XSS occurs entirely within the browser when client-side JavaScript writes attacker-controlled data into a sink such as innerHTML, document.write, or eval without proper sanitization.

An authenticated attacker with low privileges can craft a URL or webpage that manipulates the DOM environment consumed by AEM's client-side scripts. When the victim visits the crafted resource, the injected payload executes in the victim's browser under the origin of the AEM application.

Because the CVSS scope is changed, the executed script can affect resources beyond the vulnerable AEM component, including linked applications or authoring contexts trusted by the browser session. Confidentiality and integrity impacts are limited, and availability is not affected.

Root Cause

The root cause is improper neutralization of user-controllable input that is subsequently written into the DOM by client-side JavaScript. AEM does not sufficiently sanitize or encode this input before it reaches a browser sink capable of parsing HTML or executing script.

Attack Vector

Exploitation is network-based and requires the victim to visit an attacker-controlled or crafted webpage. The attacker embeds a payload in a URL fragment or query parameter that AEM client code reads and injects into the DOM. Refer to Adobe Security Advisory APSB26-98 for technical details.

Detection Methods for CVE-2026-75636

Indicators of Compromise

Web server or CDN logs showing AEM requests containing suspicious URL fragments or query parameters with <script>, javascript:, onerror=, or encoded variants such as %3Cscript%3E.
Browser telemetry showing unexpected script execution originating from AEM-hosted pages or authoring interfaces.
Outbound requests from AEM user sessions to unknown domains shortly after clicking an external link.

Detection Strategies

Deploy a Content Security Policy (CSP) in report-only mode to identify inline script violations on AEM pages and capture DOM injection attempts.
Inspect referrer chains and URL parameters in AEM access logs for encoded XSS payload patterns.
Use a Web Application Firewall (WAF) with XSS signature rules to flag requests targeting known AEM endpoints with script-like content.

Monitoring Recommendations

Correlate AEM authentication events with unusual downstream API calls made by the same session identifier.
Monitor for anomalous outbound network activity from endpoints where AEM authors and administrators operate.
Alert on browser process children spawning from AEM sessions where sensitive credentials or content are handled.

How to Mitigate CVE-2026-75636

Immediate Actions Required

Apply the security update referenced in Adobe Security Advisory APSB26-98 to all affected AEM instances.
Restrict AEM authoring interfaces to trusted networks and require VPN or zero-trust access.
Enforce phishing awareness for AEM authors and administrators, since exploitation requires visiting a crafted page.

Patch Information

Adobe released fixes for CVE-2026-75636 as part of APSB26-98. Administrators should review the advisory to identify affected AEM versions and apply the corresponding update or hotfix through the Adobe Experience Manager update channel.

Workarounds

Deploy a strict Content Security Policy that disallows inline scripts and untrusted script sources on AEM origins.
Configure a WAF to block requests containing common XSS payload patterns targeting AEM URLs.
Instruct authors to avoid clicking untrusted links while authenticated to AEM until patching is complete.

bash

# Example CSP header to reduce DOM XSS impact on AEM origins
Content-Security-Policy: default-src 'self'; \
  script-src 'self' 'nonce-RANDOM' https://trusted.cdn.example; \
  object-src 'none'; \
  base-uri 'self'; \
  frame-ancestors 'self'; \
  require-trusted-types-for 'script'