CVE-2024-26123
📋 TL;DR
This stored Cross-Site Scripting (XSS) vulnerability in Adobe Experience Manager allows attackers to inject malicious JavaScript into vulnerable form fields. When users visit pages containing these compromised fields, their browsers execute the attacker's scripts. This affects Adobe Experience Manager versions 6.5.20 and earlier.
💻 Affected Systems
- Adobe Experience Manager
📦 What is this software?
⚠️ Risk & Real-World Impact
Worst Case
Attackers could steal user session cookies, perform actions as authenticated users, redirect to malicious sites, or install malware through drive-by downloads.
Likely Case
Session hijacking, credential theft, defacement of web pages, or redirection to phishing sites.
If Mitigated
Limited impact with proper input validation, output encoding, and Content Security Policy (CSP) headers in place.
🎯 Exploit Status
Exploitation requires ability to submit data to vulnerable form fields. Stored XSS means payload persists until cleaned.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: 6.5.21 or later
Vendor Advisory: https://helpx.adobe.com/security/products/experience-manager/apsb24-28.html
Restart Required: Yes
Instructions:
1. Download Adobe Experience Manager 6.5.21 or later from Adobe's official distribution. 2. Follow Adobe's upgrade documentation for your deployment type (on-premise or cloud). 3. Apply the update to all affected instances. 4. Restart the AEM service. 5. Verify the update was successful.
🔧 Temporary Workarounds
Input Validation and Output Encoding
allImplement server-side input validation and proper output encoding for all user-supplied data in form fields.
Content Security Policy
allImplement strict Content Security Policy headers to restrict script execution sources.
🧯 If You Can't Patch
- Implement Web Application Firewall (WAF) rules to detect and block XSS payloads
- Disable or restrict access to vulnerable form fields until patching is possible
🔍 How to Verify
Check if Vulnerable:
Check Adobe Experience Manager version via AEM Web Console (/system/console) or by examining the AEM installation directory for version files.Check Version:
Check /system/console/bundles for org.apache.sling.installer.core bundle version or examine crx-quickstart/VERSION fileVerify Fix Applied:
Verify version is 6.5.21 or later and test form fields with XSS payloads to ensure they're properly sanitized.📡 Detection & Monitoring
Log Indicators:
- Unusual form submissions with script tags or JavaScript code
- Multiple failed XSS attempts in access logs
Network Indicators:
- HTTP requests containing script tags or JavaScript in form parameters
- Unexpected outbound connections from user browsers
SIEM Query:
source="aem_access.log" AND ("<script" OR "javascript:" OR "onerror=" OR "onload=")