CVE-2026-75642: Adobe Experience Manager XSS Vulnerability

CVE-2026-75642 Overview

CVE-2026-75642 is a stored Cross-Site Scripting (XSS) vulnerability in Adobe Experience Manager (AEM). A low-privileged authenticated attacker can inject malicious JavaScript into vulnerable form fields. When a victim browses to the page rendering the affected field, the injected script executes in their browser context. The issue is classified under [CWE-79] (Improper Neutralization of Input During Web Page Generation) and has a changed scope, meaning the impact extends beyond the initially vulnerable component.

Critical Impact
An authenticated attacker with low privileges can persistently inject scripts that run in other users' browsers, enabling session data theft, unauthorized actions on behalf of victims, and content manipulation across the AEM environment.

Affected Products

Adobe Experience Manager (per Adobe Security Advisory APSB26-98)
Specific affected versions are enumerated in the vendor advisory
Both AEM Cloud Service and on-premises deployments should be reviewed against the advisory

Discovery Timeline

2026-09-08 - CVE-2026-75642 published to the National Vulnerability Database
2026-09-08 - Last updated in NVD database

Technical Details for CVE-2026-75642

Vulnerability Analysis

The vulnerability is a stored XSS flaw in Adobe Experience Manager form-handling functionality. AEM stores attacker-supplied input in vulnerable form fields without sufficient output encoding or input sanitization. When another user later loads a page that renders the stored content, their browser interprets the payload as executable JavaScript rather than inert data.

The scope change indicates that the vulnerable component and the impacted component differ. A payload stored through a lower-privileged authoring or form workflow can execute in the browser session of higher-privileged users or unrelated visitors. Exploitation requires attacker authentication with low privileges and user interaction, since the victim must navigate to the page hosting the malicious field.

Successful exploitation can lead to session token theft, authenticated request forgery inside the AEM console, defacement of managed content, and pivoting into administrative workflows if a privileged user views the poisoned page.

Root Cause

The root cause is improper neutralization of user-controlled input during web page generation [CWE-79]. Input submitted to certain form fields is persisted and later reflected into HTML responses without context-appropriate escaping. Because AEM stores the payload server-side, the flaw is a persistent (stored) XSS rather than a reflected variant.

Attack Vector

The attack is network-reachable and requires an authenticated low-privileged account plus victim interaction. An attacker submits a crafted payload into a vulnerable form field through the normal AEM interface. AEM stores the payload. A subsequent user visiting the affected page triggers script execution in their browser under the AEM origin.

No verified proof-of-concept code is publicly available. See the Adobe Security Advisory APSB26-98 for vendor-provided technical detail.

// No public exploit code is available for CVE-2026-75642.
// Refer to Adobe Security Advisory APSB26-98 for vendor guidance.

Detection Methods for CVE-2026-75642

Indicators of Compromise

Form-field values or JCR (Java Content Repository) node properties containing HTML tags such as <script>, <img onerror=...>, or javascript: URIs.
Unexpected outbound HTTP requests from author or publish instances to attacker-controlled domains following page loads.
Browser console errors or Content Security Policy violation reports originating from AEM-hosted pages.

Detection Strategies

Audit AEM content repositories for stored HTML or JavaScript inside form-field properties that should contain plaintext only.
Review AEM request logs for POST requests to form endpoints containing encoded script payloads submitted by low-privileged accounts.
Correlate authoring activity with anomalous session behavior from users who subsequently viewed the affected pages.

Monitoring Recommendations

Enable and monitor Content Security Policy (CSP) violation reporting on AEM-delivered pages.
Alert on new or modified form components submitted by non-administrative users.
Track EPSS trending for CVE-2026-75642; the current EPSS probability is 0.201%, but exposure grows if a public PoC emerges.

How to Mitigate CVE-2026-75642

Immediate Actions Required

Apply the fixed AEM version identified in Adobe Security Advisory APSB26-98.
Inventory AEM instances, including author, publish, and dispatcher tiers, and confirm patch status.
Review recent form submissions from low-privileged accounts for stored payloads and remediate affected content.

Patch Information

Adobe has published fixes as part of advisory APSB26-98. Administrators should upgrade to the vendor-specified patched build for their AEM deployment model (Cloud Service, AMS, or on-premises) and re-verify that vulnerable form components render encoded output after the update.

Workarounds

Restrict form-authoring and content-submission permissions to trusted user groups until the patch is applied.
Enforce a strict Content Security Policy that disallows inline scripts and untrusted script sources on AEM-delivered pages.
Deploy a web application firewall rule to block script tags and common XSS payload patterns in form submissions.

bash

# Example dispatcher filter to block obvious XSS payloads in form POSTs
/0100 { /type "deny" /method "POST" /url "*<script*" }
/0101 { /type "deny" /method "POST" /url "*javascript:*" }