CVE-2025-53514
📋 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 its webhook endpoint. This affects organizations using the vulnerable plugin version to integrate Mattermost with Confluence. The vulnerability can lead to service disruption but does not allow data theft or remote code execution.
💻 Affected Systems
- Mattermost Confluence Plugin
📦 What is this software?
Confluence by Mattermost
⚠️ Risk & Real-World Impact
Worst Case
Complete plugin crash leading to disruption of Mattermost-Confluence integration, potentially requiring manual restart or server intervention to restore functionality.
Likely Case
Temporary service degradation or intermittent plugin failures when attackers send crafted requests to the webhook endpoint.
If Mitigated
Minimal impact with proper network controls and monitoring in place to detect and block malicious requests.
🎯 Exploit Status
Exploitation requires sending specially crafted requests to the plugin's webhook endpoint. No authentication bypass is involved.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: 1.5.0
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
Restrict Webhook Access
allLimit access to the plugin's webhook endpoint using network controls or web application firewall rules.
Disable Plugin Temporarily
mattermostTemporarily disable the Confluence plugin until patching can be completed.
/plugins disable com.mattermost.confluence
🧯 If You Can't Patch
- Implement rate limiting on webhook endpoints to prevent sustained attack attempts
- Deploy WAF rules to filter malformed request bodies targeting the plugin endpoint
🔍 How to Verify
Check if Vulnerable:
Check the plugin version in Mattermost System Console > Plugin Management > Confluence PluginCheck Version:
/plugin list | grep confluenceVerify Fix Applied:
Confirm plugin version is 1.5.0 or higher and test webhook functionality📡 Detection & Monitoring
Log Indicators:
- Multiple 400/500 errors from webhook endpoint
- Plugin crash logs in Mattermost logs
- Unusual request patterns to /plugins/com.mattermost.confluence/webhook
Network Indicators:
- High volume of malformed POST requests to plugin webhook endpoint
- Unusual traffic spikes from single IPs
SIEM Query:
source="mattermost" AND ("plugin crash" OR "webhook error" OR "confluence plugin")