CVE-2026-1009
📋 TL;DR
A stored cross-site scripting vulnerability in Altium Forum allows authenticated attackers to inject malicious JavaScript into forum posts. When other users view these posts, the script executes in their authenticated Altium 365 session, potentially compromising workspace data including design files and settings. All users of the affected Altium Forum who view malicious posts are at risk.
💻 Affected Systems
- Altium Forum
📦 What is this software?
⚠️ Risk & Real-World Impact
Worst Case
Complete compromise of Altium 365 workspace data including theft of intellectual property design files, unauthorized access to workspace settings, and potential lateral movement within the organization's Altium ecosystem.
Likely Case
Unauthorized access to sensitive design files and workspace configurations, data exfiltration, and potential session hijacking for affected users.
If Mitigated
Limited impact with proper input validation and output encoding, potentially only affecting forum functionality without compromising core workspace data.
🎯 Exploit Status
Exploitation requires authenticated forum access and victim interaction (viewing malicious post)
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: Check Altium security advisory for specific version
Vendor Advisory: https://www.altium.com/platform/security-compliance/security-advisories
Restart Required: No
Instructions:
1. Review Altium security advisory for patch details
2. Apply the latest Altium Forum update
3. Verify input sanitization is implemented for all user-generated content
🔧 Temporary Workarounds
Disable JavaScript in Forum Posts
allImplement content security policy to restrict JavaScript execution in forum content
Content-Security-Policy: script-src 'self'
Temporary Forum Access Restriction
allLimit forum access to trusted users only while awaiting patch
🧯 If You Can't Patch
- Implement web application firewall with XSS protection rules
- Monitor forum posts for suspicious JavaScript content and alert on detection
🔍 How to Verify
Check if Vulnerable:
Test forum post functionality with XSS payloads like <script>alert('test')</script> and check if script executesCheck Version:
Check Altium Forum version in admin panel or contact Altium supportVerify Fix Applied:
Retest with same XSS payloads to confirm scripts are properly sanitized and do not execute📡 Detection & Monitoring
Log Indicators:
- Unusual forum post creation patterns
- Posts containing script tags or JavaScript code
- Multiple failed login attempts followed by forum activity
Network Indicators:
- Outbound connections to suspicious domains from forum sessions
- Unusual data transfers from Altium workspace
SIEM Query:
source="altium_forum" AND (message="*<script>*" OR message="*javascript:*")