CVE-2026-48264: Adobe Experience Manager XSS Vulnerability

CVE-2026-48264 Overview

CVE-2026-48264 is a DOM-based Cross-Site Scripting (XSS) vulnerability affecting Adobe Experience Manager (AEM). The flaw exists in AEM versions 6.5.24, LTS SP1, 2026.04, and earlier releases. An attacker can manipulate the Document Object Model (DOM) to execute arbitrary JavaScript in the victim's browser context. Exploitation requires user interaction, where the victim must visit a crafted webpage. The vulnerability carries a scope change, allowing the impact to extend beyond the vulnerable component. Adobe categorizes this issue under CWE-79 (Improper Neutralization of Input During Web Page Generation).

Critical Impact

Successful exploitation enables attackers to execute malicious JavaScript in the victim's browser, potentially leading to session hijacking, credential theft, or unauthorized actions within the AEM environment.

Affected Products

• Adobe Experience Manager 6.5.24 and earlier
• Adobe Experience Manager LTS SP1 and earlier
• Adobe Experience Manager 2026.04 and earlier (including AEM Cloud Service)

Discovery Timeline

• 2026-06-09 - CVE-2026-48264 published to the National Vulnerability Database (NVD)
• 2026-06-10 - Last updated in NVD database

Technical Details for CVE-2026-48264

Vulnerability Analysis

The vulnerability is a DOM-based XSS issue residing in client-side JavaScript within Adobe Experience Manager. Unlike reflected or stored XSS, DOM-based XSS executes entirely in the victim's browser without server-side request modification. The vulnerable JavaScript reads attacker-controlled data from a DOM source and writes it to a sink that interprets the value as executable script.

The flaw requires authenticated low-privilege access combined with victim interaction. An attacker must lure an authenticated AEM user to a crafted page containing the malicious DOM payload. The scope change indicates that successful exploitation impacts resources beyond the AEM component itself, such as adjacent applications sharing the browser origin or session context.

Root Cause

The root cause is improper neutralization of input during web page generation in client-side script handling. AEM components pass untrusted data from sources such as location.hash, document.URL, or window.name directly into DOM sinks like innerHTML, document.write, or eval without proper sanitization or output encoding.

Attack Vector

The attack proceeds through a network-based vector with low attack complexity. An attacker authenticates to AEM with low-privilege credentials and crafts a URL or webpage containing a malicious DOM payload. When a targeted user visits the crafted page, the embedded JavaScript executes within the AEM origin. The script can then exfiltrate authentication tokens, perform unauthorized API calls, or manipulate page content visible to the victim.

No verified exploitation code is publicly available. For technical details, refer to the Adobe Security Advisory APSB26-56.

Detection Methods for CVE-2026-48264

Indicators of Compromise

• Unexpected JavaScript execution events in browser logs originating from AEM-hosted pages
• Anomalous URL fragments or query parameters containing encoded <script>, javascript:, or HTML entity payloads accessed against AEM endpoints
• Outbound HTTP requests from authenticated AEM sessions to attacker-controlled domains following user navigation events

Detection Strategies

• Inspect AEM web server access logs for requests containing suspicious URL fragments, hash parameters, or encoded script content targeting AEM author and publish instances
• Deploy Content Security Policy (CSP) reporting endpoints to capture script execution violations originating from AEM pages
• Correlate authentication events with subsequent abnormal outbound network connections from user workstations accessing AEM

Monitoring Recommendations

• Enable detailed request logging on AEM dispatcher and publish tiers, retaining query strings and referrer headers
• Monitor authenticated AEM user sessions for unusual privilege actions performed shortly after page navigation
• Track browser telemetry from endpoints accessing AEM authoring interfaces for script injection patterns

How to Mitigate CVE-2026-48264

Immediate Actions Required

• Apply the Adobe security updates referenced in APSB26-56 to all affected AEM instances, including author, publish, and Cloud Service environments
• Audit AEM user accounts and revoke unnecessary low-privilege access that could be leveraged in exploitation
• Train content authors and administrators to avoid clicking untrusted links while authenticated to AEM

Patch Information

Adobe released fixes for this vulnerability in the Adobe Security Advisory APSB26-56. Customers running AEM 6.5.24, LTS SP1, 2026.04, or earlier must upgrade to the patched versions listed in the advisory. AEM as a Cloud Service customers should ensure their instances are running the latest service release.

Workarounds

• Implement a strict Content Security Policy (CSP) that disallows inline script execution and restricts script sources to trusted origins
• Deploy a web application firewall (WAF) rule set to filter requests containing common DOM XSS payload patterns targeting AEM endpoints
• Restrict AEM author instance access to trusted network segments through VPN or IP allowlisting until patches are applied

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