CVE-2024-39830
📋 TL;DR
Mattermost versions with shared channels enabled are vulnerable to a timing attack that allows retrieval of remote cluster tokens. Attackers can exploit this by measuring response time differences during token comparisons. This affects organizations using Mattermost with shared channels functionality.
💻 Affected Systems
- Mattermost
📦 What is this software?
Mattermost by Mattermost
Mattermost by Mattermost
Mattermost by Mattermost
Mattermost by Mattermost
⚠️ Risk & Real-World Impact
Worst Case
An attacker obtains remote cluster tokens, potentially gaining unauthorized access to connected clusters, leading to data exfiltration or lateral movement across the Mattermost infrastructure.
Likely Case
Attackers with network access to Mattermost servers could retrieve tokens over time, compromising the security of shared channels and potentially accessing sensitive communications.
If Mitigated
With proper network segmentation and monitoring, exploitation would be detected before significant damage occurs, limiting impact to isolated systems.
🎯 Exploit Status
Requires network access to Mattermost server and ability to perform precise timing measurements. Exploitation requires knowledge of timing attack techniques.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: 9.8.1, 9.7.5, 9.6.3, 9.5.6
Vendor Advisory: https://mattermost.com/security-updates
Restart Required: Yes
Instructions:
1. Backup Mattermost configuration and data. 2. Download patched version from Mattermost downloads. 3. Stop Mattermost service. 4. Install patched version. 5. Restart Mattermost service. 6. Verify version and functionality.
🔧 Temporary Workarounds
Disable Shared Channels
allTemporarily disable shared channels feature to eliminate vulnerability vector
Edit config.json: set "EnableSharedChannels" to false
Restart Mattermost service
🧯 If You Can't Patch
- Implement network segmentation to restrict access to Mattermost servers
- Enable detailed logging and monitoring for unusual authentication patterns
🔍 How to Verify
Check if Vulnerable:
Check Mattermost version via web interface Admin Console > System Console > About or run: mattermost versionCheck Version:
mattermost versionVerify Fix Applied:
Verify version is 9.8.1, 9.7.5, 9.6.3, or 9.5.6 or higher📡 Detection & Monitoring
Log Indicators:
- Multiple failed authentication attempts with timing patterns
- Unusual remote cluster connection attempts
Network Indicators:
- Repeated authentication requests to Mattermost API endpoints
- Abnormal timing patterns in network traffic
SIEM Query:
source="mattermost" AND (event="authentication_failure" OR event="remote_cluster_auth") | stats count by src_ip