CVE-2025-62787
📋 TL;DR
A buffer over-read vulnerability in Wazuh's DecodeWinevt() function allows compromised agents to trigger read operations beyond allocated buffer boundaries. Attackers can exploit this by sending specially crafted messages to the Wazuh manager, potentially accessing sensitive data. This affects Wazuh installations prior to version 4.10.2 with analysisd.debug=2 configuration enabled.
💻 Affected Systems
- Wazuh
📦 What is this software?
Wazuh by Wazuh
⚠️ Risk & Real-World Impact
Worst Case
Sensitive information disclosure including potentially credentials, configuration data, or other memory contents from the Wazuh manager process.
Likely Case
Limited information disclosure from memory buffers, potentially exposing debug information or partial data structures.
If Mitigated
No impact if debug mode is disabled or proper network segmentation prevents agent compromise.
🎯 Exploit Status
Requires ability to send crafted messages to Wazuh manager, typically through compromised agent. Debug configuration must be enabled for data leakage.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: 4.10.2
Vendor Advisory: https://github.com/wazuh/wazuh/security/advisories/GHSA-3hhq-5367-98q6
Restart Required: Yes
Instructions:
1. Backup current configuration. 2. Update Wazuh manager to version 4.10.2 or later using package manager. 3. Restart Wazuh services. 4. Verify successful update.
🔧 Temporary Workarounds
Disable Debug Mode
linuxSet analysisd.debug to 0 or remove debug configuration to prevent data leakage
sed -i 's/analysisd.debug=2/analysisd.debug=0/g' /var/ossec/etc/ossec.conf
systemctl restart wazuh-manager
Network Segmentation
allRestrict agent-manager communication to trusted networks only
🧯 If You Can't Patch
- Disable analysisd.debug configuration (set to 0)
- Implement strict network controls between agents and manager
🔍 How to Verify
Check if Vulnerable:
Check Wazuh version and debug configuration: grep -i 'analysisd.debug' /var/ossec/etc/ossec.conf && wazuh-manager -vCheck Version:
wazuh-manager -vVerify Fix Applied:
Verify version is 4.10.2 or later: wazuh-manager -v | grep -q '4.10.2' && echo 'Patched'📡 Detection & Monitoring
Log Indicators:
- Unusual agent messages with malformed winevt data
- Debug logs showing buffer access errors
Network Indicators:
- Abnormal agent-to-manager message patterns
- Unexpected data transfers from manager
SIEM Query:
source="wazuh" AND ("DecodeWinevt" OR "buffer" OR "debug=2")