CVE-2026-106629: Adobe Experience Manager XSS Vulnerability

CVE-2026-106629 Overview

Adobe Experience Manager (AEM) contains a stored Cross-Site Scripting (XSS) vulnerability [CWE-79] in form field handling. Attackers can inject malicious JavaScript into vulnerable form fields that persists in the application. When a victim loads the page containing the tainted field, the script executes in their browser context. Successful exploitation can lead to session hijacking, account takeover, or elevated access within the AEM environment. The vulnerability has a changed scope, meaning the injected code can affect resources beyond the vulnerable component itself.

Critical Impact
Stored XSS in Adobe Experience Manager allows attackers to execute arbitrary JavaScript in victims' browsers, enabling session theft and account compromise with no authentication required to inject the payload.

Affected Products

Adobe Experience Manager (AEM)
Refer to Adobe Security Advisory APSB26-152 for specific affected versions
All AEM instances exposing vulnerable form fields to untrusted input

Discovery Timeline

2026-10-13 - CVE-2026-106629 published to the National Vulnerability Database (NVD)
2026-10-14 - Last updated in NVD database

Technical Details for CVE-2026-106629

Vulnerability Analysis

The vulnerability is a stored (persistent) Cross-Site Scripting flaw within Adobe Experience Manager form handling components. Attackers submit crafted input into vulnerable form fields, and AEM stores that input without sufficient output encoding or sanitization. When any user subsequently renders the affected page, the browser executes the injected JavaScript in the context of the AEM origin.

Because the scope is changed, the executed script can access resources outside the vulnerable component's security boundary. This enables attackers to pivot into administrative interfaces or related applications sharing the AEM session. Impact to confidentiality and integrity is high, while availability is unaffected.

Root Cause

The root cause is improper neutralization of input during web page generation, classified under [CWE-79]. AEM accepts user-controlled values in form fields and renders them back to subsequent viewers without proper HTML entity encoding or script tag filtering. The failure to apply contextual output encoding allows raw JavaScript payloads to execute when the stored content is served.

Attack Vector

Exploitation requires network access to the AEM instance and user interaction from a victim loading the affected page. The attacker does not need authentication to inject the payload. A typical attack chain involves the attacker submitting a crafted payload containing JavaScript into a vulnerable form field, AEM persisting that payload in its content repository, and a privileged user later visiting the page where the stored script fires in their session context. The attacker then exfiltrates session tokens, performs actions on behalf of the victim, or escalates access across the AEM environment.

No verified public proof-of-concept code is available at this time. Refer to the Adobe Security Advisory APSB26-152 for vendor technical details.

Detection Methods for CVE-2026-106629

Indicators of Compromise

Form field values in the AEM repository containing <script>, javascript:, onerror=, onload=, or encoded script delimiters
Unexpected outbound HTTP requests from authenticated AEM user sessions to attacker-controlled domains
Browser console errors or Content Security Policy (CSP) violations originating from AEM-served pages
Anomalous session reuse from geographically distant IP addresses shortly after a user accessed a form page

Detection Strategies

Audit AEM content repository nodes for stored HTML or script content in fields intended to hold plain text
Deploy a Web Application Firewall (WAF) rule set targeting common XSS payload patterns submitted to AEM form endpoints
Enable and monitor CSP report-only directives to surface inline script execution attempts
Correlate form submission events with subsequent page render events to identify payload persistence

Monitoring Recommendations

Log and alert on POST requests to AEM form submission endpoints containing script-related tokens
Monitor administrator and content author sessions for unusual client-side activity following page loads
Review AEM access logs for high-privilege account activity sourced from unfamiliar user agents or IP addresses
Track changes to form definitions and sling resource types that handle user input rendering

How to Mitigate CVE-2026-106629

Immediate Actions Required

Apply the Adobe security update referenced in APSB26-152 to all AEM instances
Audit existing form field content for previously injected payloads and purge malicious entries
Rotate session tokens and credentials for any users who accessed affected forms before patching
Restrict public access to AEM authoring and form submission endpoints where feasible

Patch Information

Adobe has released a security update addressing this vulnerability. Consult Adobe Security Advisory APSB26-152 for the exact fixed versions and installation guidance. Apply the vendor-supplied patch to all AEM Author, Publish, and Dispatcher tiers.

Workarounds

Deploy a WAF rule to block form submissions containing script tags, event handlers, and javascript: URIs
Enforce a strict Content Security Policy that disallows inline scripts and restricts script sources to trusted origins
Configure AEM Dispatcher filters to reject requests containing suspicious payload patterns
Limit form field input to expected character sets and lengths via server-side validation

bash

# Example AEM Dispatcher filter to block script-like payloads in form POSTs
/0100 { /type "deny" /method "POST" /url "*<script*" }
/0101 { /type "deny" /method "POST" /url "*javascript:*" }
/0102 { /type "deny" /method "POST" /url "*onerror=*" }

# Example Content Security Policy response header
Content-Security-Policy: default-src 'self'; script-src 'self'; object-src 'none'; base-uri 'self'