CVE-2026-109415: Adobe Experience Manager XSS Vulnerability

CVE-2026-109415 Overview

CVE-2026-109415 is a stored Cross-Site Scripting (XSS) vulnerability affecting Adobe Experience Manager (AEM). A low-privileged authenticated attacker can inject malicious JavaScript into vulnerable form fields. The payload executes in the browser of any victim who views the page containing the compromised field. The scope is changed, meaning the impact extends beyond the vulnerable component to other resources accessible to the victim. The flaw is tracked under CWE-79: Improper Neutralization of Input During Web Page Generation.

Critical Impact
Authenticated attackers with low privileges can store JavaScript in AEM form fields, leading to session hijacking, credential theft, or unauthorized actions in the context of victim users browsing the affected pages.

Affected Products

Adobe Experience Manager (AEM) — refer to Adobe Security Bulletin APSB26-152 for the specific affected versions
Adobe Experience Manager Cloud Service deployments as listed in the vendor advisory
Adobe Experience Manager on-premise and Adobe Managed Services instances within the advisory scope

Discovery Timeline

2026-10-13 - CVE-2026-109415 published to the National Vulnerability Database
2026-10-14 - Last updated in NVD database

Technical Details for CVE-2026-109415

Vulnerability Analysis

The vulnerability resides in form-field handling within Adobe Experience Manager. User-supplied input placed into certain form fields is persisted and later rendered to other users without adequate output encoding or sanitization. When a victim browses to a page that renders the stored value, the attacker-controlled JavaScript executes in the victim's browser session under the origin of the AEM application.

Because the attack is stored rather than reflected, no social engineering link is required for the payload itself. The attacker needs only authenticated access with low privileges to seed the payload, and victims need only visit the rendering page for execution to occur. User interaction is required for the victim, but not for the attacker.

The changed scope indicator shows that successful exploitation can affect resources beyond the vulnerable component, including other authenticated users and administrative sessions that render the stored content.

Root Cause

The root cause is improper neutralization of input during web page generation [CWE-79]. AEM accepts input into form fields without stripping or encoding active HTML and JavaScript constructs. The persisted content is later emitted into HTML responses in a context where the browser interprets it as executable script rather than inert text.

Attack Vector

The attack vector is network-based and requires authentication at a low privilege level. An attacker with authoring, contributor, or similar form-editing rights submits a crafted payload into a susceptible form field. Any user — including higher-privileged administrators — who later views the page containing the field triggers execution of the attacker's script. Typical post-exploitation outcomes include session token theft, forced actions via the AEM UI, and pivoting into content administration workflows.

No verified proof-of-concept code is publicly available at this time. See Adobe Security Bulletin APSB26-152 for vendor-provided technical context.

Detection Methods for CVE-2026-109415

Indicators of Compromise

Stored form-field content containing <script>, onerror=, onload=, javascript: URIs, or encoded variants such as <script>
Outbound HTTP requests from administrative sessions to attacker-controlled domains following page views in AEM authoring or publishing instances
Unexpected modifications to AEM content nodes by low-privileged author accounts outside normal working patterns

Detection Strategies

Inspect AEM request and response logs for form submissions containing HTML tags, event handlers, or script constructs in text fields
Review AEM audit logs for content changes committed by low-privileged users that touch form components across multiple pages
Correlate browser-side error reports and Content Security Policy violations originating from AEM-hosted pages

Monitoring Recommendations

Enable and ship AEM access.log, audit.log, and error.log to a centralized analytics platform for continuous review
Monitor privileged administrator sessions for anomalous navigation patterns and unexpected API calls shortly after viewing author-created content
Alert on new or modified content nodes containing script-related keywords or encoded script payloads

How to Mitigate CVE-2026-109415

Immediate Actions Required

Apply the Adobe security update referenced in Adobe Security Bulletin APSB26-152 to all affected AEM instances
Audit existing form-field content for stored script payloads and remove or neutralize any suspicious entries
Review and tighten AEM user permissions so that only trusted accounts can author or edit form components

Patch Information

Adobe has released fixed versions of Adobe Experience Manager addressing CVE-2026-109415. Consult Adobe Security Bulletin APSB26-152 for the exact fixed version numbers, download locations, and upgrade procedures applicable to AEM Cloud Service and on-premise deployments.

Workarounds

Enforce a strict Content Security Policy on AEM-delivered pages that disallows inline scripts and restricts script sources to known-good origins
Place a web application firewall in front of AEM to inspect and block form submissions containing HTML tags or script constructs in text fields
Rotate authentication tokens and session cookies for administrative accounts after patching to invalidate any session artifacts potentially captured during exposure

bash

# Example Content Security Policy header for AEM Dispatcher as a defense-in-depth control
Header always set Content-Security-Policy "default-src 'self'; script-src 'self'; object-src 'none'; base-uri 'self'; frame-ancestors 'self'"