CVE-2023-28470
📋 TL;DR
Couchbase Server versions 5 through 7.1.3 expose the nsstats endpoint without requiring authentication. This allows unauthenticated attackers to access server statistics and potentially gather information about the database environment. All Couchbase Server deployments within the affected version range are vulnerable if the endpoint is accessible.
💻 Affected Systems
- Couchbase Server
📦 What is this software?
⚠️ Risk & Real-World Impact
Worst Case
Information disclosure could reveal sensitive operational details, cluster topology, performance metrics, and potentially aid in further attacks by exposing system configuration.
Likely Case
Unauthenticated access to server statistics, allowing reconnaissance and information gathering about the database environment.
If Mitigated
Limited impact with proper network segmentation and access controls preventing external access to the endpoint.
🎯 Exploit Status
Exploitation requires only HTTP access to the vulnerable endpoint - no authentication or special tools needed.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: 7.1.4 and later
Vendor Advisory: https://docs.couchbase.com/server/current/release-notes/relnotes.html
Restart Required: Yes
Instructions:
1. Download Couchbase Server 7.1.4 or later from official sources. 2. Backup all data and configuration. 3. Stop Couchbase Server services. 4. Install the updated version. 5. Restart Couchbase Server services. 6. Verify the update was successful.
🔧 Temporary Workarounds
Network Access Control
linuxRestrict network access to Couchbase Server endpoints using firewall rules
iptables -A INPUT -p tcp --dport 8091 -s trusted_network -j ACCEPT
iptables -A INPUT -p tcp --dport 8091 -j DROP
Reverse Proxy Authentication
allPlace Couchbase Server behind a reverse proxy that requires authentication
🧯 If You Can't Patch
- Implement strict network segmentation to prevent unauthorized access to Couchbase Server endpoints
- Deploy web application firewall rules to block access to /nsstats endpoint
🔍 How to Verify
Check if Vulnerable:
Attempt to access http://[couchbase-server]:8091/nsstats without authentication. If it returns statistics data, the system is vulnerable.Check Version:
curl -s http://localhost:8091/pools | grep -o '"version":"[^"]*"'Verify Fix Applied:
After patching, attempt the same access. You should receive an authentication prompt or access denied response.📡 Detection & Monitoring
Log Indicators:
- Unauthenticated access attempts to /nsstats endpoint
- HTTP 200 responses to /nsstats from unauthenticated sources
Network Indicators:
- Unusual traffic patterns to port 8091 from unauthorized sources
- GET requests to /nsstats endpoint
SIEM Query:
source="couchbase.log" AND (uri_path="/nsstats" AND http_status=200 AND NOT authenticated_user=*)🔗 References
- https://docs.couchbase.com/server/current/release-notes/relnotes.html
- https://forums.couchbase.com/tags/security
- https://www.couchbase.com/alerts/
- https://www.couchbase.com/downloads
- https://docs.couchbase.com/server/current/release-notes/relnotes.html
- https://forums.couchbase.com/tags/security
- https://www.couchbase.com/alerts/
- https://www.couchbase.com/downloads
