CVE-2025-54463
📋 TL;DR
The Mattermost Confluence Plugin before version 1.5.0 contains an improper input validation vulnerability that allows attackers to crash the plugin by sending malformed requests to the server webhook endpoint. This affects organizations using Mattermost with the Confluence plugin integration. The vulnerability can lead to denial of service for the plugin functionality.
💻 Affected Systems
- Mattermost Confluence Plugin
📦 What is this software?
Confluence by Mattermost
⚠️ Risk & Real-World Impact
Worst Case
Complete denial of service for the Confluence plugin functionality, disrupting integration between Mattermost and Confluence systems and potentially affecting business workflows.
Likely Case
Temporary disruption of Confluence integration in Mattermost, requiring plugin restart or server intervention to restore functionality.
If Mitigated
Minimal impact with proper rate limiting, input validation, and monitoring in place to detect and block malicious requests.
🎯 Exploit Status
Exploitation requires sending specially crafted requests to the webhook endpoint. No authentication bypass is mentioned, but the advisory doesn't specify if authentication is required for the vulnerable endpoint.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: 1.5.0 or later
Vendor Advisory: https://mattermost.com/security-updates
Restart Required: No
Instructions:
1. Access Mattermost System Console. 2. Navigate to Plugin Management. 3. Update Confluence Plugin to version 1.5.0 or later. 4. Verify plugin functionality after update.
🔧 Temporary Workarounds
Rate Limiting Webhook Endpoints
allImplement rate limiting on the webhook endpoint to prevent repeated malicious requests from causing denial of service.
Configure rate limiting in Mattermost System Console under Security > Rate Limiting
Set appropriate limits for webhook endpoints
Disable Confluence Plugin
allTemporarily disable the Confluence plugin if not critically needed while awaiting patch deployment.
mmctl plugin disable com.mattermost.confluence
🧯 If You Can't Patch
- Implement network-level controls to restrict access to webhook endpoints
- Monitor logs for unusual patterns of requests to the Confluence plugin webhook endpoint
🔍 How to Verify
Check if Vulnerable:
Check the Confluence plugin version in Mattermost System Console > Plugin Management. If version is below 1.5.0, the system is vulnerable.Check Version:
mmctl plugin list | grep confluenceVerify Fix Applied:
Verify plugin version shows 1.5.0 or higher in System Console. Test Confluence integration functionality to ensure it works properly.📡 Detection & Monitoring
Log Indicators:
- Multiple 400/500 errors from Confluence plugin webhook endpoint
- Unusual request patterns to /plugins/com.mattermost.confluence/webhook
- Plugin crash/restart events in Mattermost logs
Network Indicators:
- High volume of requests to Confluence plugin webhook endpoint
- Malformed POST requests to plugin endpoints
SIEM Query:
source="mattermost" AND ("confluence plugin" OR "com.mattermost.confluence") AND (error OR crash OR "400" OR "500")