CVE-2025-20388
📋 TL;DR
This vulnerability allows authenticated users with the 'change_authentication' capability to enumerate internal IP addresses and network ports when adding search peers in Splunk distributed environments. It affects Splunk Enterprise versions below 10.0.1, 9.4.6, 9.3.8, and 9.2.10, and Splunk Cloud Platform versions below specific patch levels. The impact is limited to information disclosure of internal network topology.
💻 Affected Systems
- Splunk Enterprise
- Splunk Cloud Platform
📦 What is this software?
Splunk by Splunk
Splunk by Splunk
Splunk by Splunk
Splunk by Splunk
⚠️ Risk & Real-World Impact
Worst Case
An attacker with legitimate 'change_authentication' privileges could map internal network infrastructure, potentially facilitating lateral movement or targeted attacks against discovered services.
Likely Case
Privileged users inadvertently or intentionally discovering internal network information that should remain hidden, potentially violating network segmentation principles.
If Mitigated
Minimal impact as the vulnerability requires high-privilege access and only reveals network information, not allowing direct system compromise.
🎯 Exploit Status
Exploitation requires legitimate access with the 'change_authentication' capability and involves normal administrative actions that reveal additional information.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: Splunk Enterprise: 10.0.1, 9.4.6, 9.3.8, 9.2.10 or later; Splunk Cloud Platform: 10.1.2507.4, 10.0.2503.7, 9.3.2411.116 or later
Vendor Advisory: https://advisory.splunk.com/advisories/SVD-2025-1207
Restart Required: Yes
Instructions:
1. Download appropriate patch version from Splunk downloads portal. 2. Backup current installation. 3. Stop Splunk services. 4. Apply patch following Splunk upgrade documentation. 5. Restart Splunk services. 6. Verify version and functionality.
🔧 Temporary Workarounds
Restrict 'change_authentication' capability
allRemove or restrict the 'change_authentication' capability from user roles that don't absolutely require it for their job functions.
splunk edit user <username> -role <role_without_change_auth>
splunk edit role <rolename> -capability remove change_authentication
Implement network segmentation
allEnsure Splunk search heads and indexers are properly segmented to limit the value of internal IP/port enumeration.
🧯 If You Can't Patch
- Review and minimize users with 'change_authentication' capability to only essential administrators
- Implement strict monitoring and alerting for search peer configuration changes
🔍 How to Verify
Check if Vulnerable:
Check Splunk version via web interface (Settings > Server Info) or CLI. Compare against affected versions list.Check Version:
splunk versionVerify Fix Applied:
Verify version is at or above patched versions. Test that adding search peers no longer reveals internal IP/port information beyond what's necessary.📡 Detection & Monitoring
Log Indicators:
- Audit logs showing search peer addition/modification by users with 'change_authentication' capability
- Unusual frequency of search peer configuration changes
Network Indicators:
- Unexpected network scans originating from Splunk search heads
- Connection attempts to discovered internal IPs/ports
SIEM Query:
index=_audit action=edit_search_peer user=* | stats count by user, src_ip