CVE-2025-27379
📋 TL;DR
A stored cross-site scripting vulnerability in Altium AES 7.0.3 allows authenticated attackers to inject malicious JavaScript into schematic descriptions. When the BOM Viewer renders affected content, the script executes in victims' browsers. This affects organizations using Altium AES 7.0.3 for electronic design.
💻 Affected Systems
- Altium AES (Altium Enterprise Server)
📦 What is this software?
⚠️ Risk & Real-World Impact
Worst Case
Attackers could steal session cookies, redirect users to malicious sites, perform actions on behalf of authenticated users, or install malware through drive-by downloads.
Likely Case
Attackers with access to create/modify schematics could compromise other users' sessions, potentially accessing sensitive design data or performing unauthorized actions.
If Mitigated
With proper input validation and output encoding, malicious scripts would be rendered harmless as text rather than executable code.
🎯 Exploit Status
Exploitation requires authenticated access to create/modify schematics. The attack vector is straightforward once access is obtained.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: Check vendor advisory for specific patched version
Vendor Advisory: https://www.altium.com/platform/security-compliance/security-advisories
Restart Required: Yes
Instructions:
1. Review the Altium security advisory for patch details
2. Download and install the patched version from Altium
3. Restart the Altium AES service
4. Verify the fix by testing XSS payloads in description fields
🔧 Temporary Workarounds
Input Validation Filter
allImplement server-side input validation to sanitize HTML/JavaScript in description fields
Implement input sanitization in schematic description processing code
Output Encoding
allApply proper HTML encoding to description field output in BOM Viewer
Encode user-controlled data using HTML entity encoding before rendering
🧯 If You Can't Patch
- Restrict schematic creation/modification permissions to trusted users only
- Implement web application firewall (WAF) rules to block XSS payloads in description fields
🔍 How to Verify
Check if Vulnerable:
Test by entering a simple XSS payload like <script>alert('test')</script> in a schematic description field and viewing it in BOM ViewerCheck Version:
Check Altium AES version in administration console or via altium --version commandVerify Fix Applied:
After patching, test the same XSS payload - it should display as plain text rather than executing JavaScript📡 Detection & Monitoring
Log Indicators:
- Unusual schematic modifications
- Multiple failed login attempts followed by schematic edits
- Schematic descriptions containing script tags or JavaScript code
Network Indicators:
- Unexpected outbound connections from user browsers after viewing BOMs
- Suspicious JavaScript payloads in HTTP requests to schematic endpoints
SIEM Query:
source="altium_logs" AND (description="*<script>*" OR description="*javascript:*")