CVE-2025-62785: Wazuh Platform DOS Vulnerability

CVE-2025-62785 Overview

CVE-2025-62785 is a Null Pointer Dereference vulnerability affecting Wazuh, a free and open source platform used for threat prevention, detection, and response. The vulnerability exists in the fillData() function implementation, which fails to check whether a value is NULL before calling os_strdup() on it. A compromised agent can exploit this flaw to crash the analysisd daemon by sending a specially crafted message to the Wazuh manager.

Critical Impact

An attacker who is able to craft and send an agent message to the Wazuh manager can cause the analysisd service to crash, rendering the security monitoring platform unavailable and potentially creating a blind spot in organizational threat detection capabilities.

Affected Products

• Wazuh versions prior to 4.10.2
• Wazuh Manager deployments accepting agent connections
• Wazuh analysisd daemon component

Discovery Timeline

• 2025-10-29 - CVE-2025-62785 published to NVD
• 2025-11-03 - Last updated in NVD database

Technical Details for CVE-2025-62785

Vulnerability Analysis

This vulnerability is classified under CWE-252 (Unchecked Return Value), which manifests as a Null Pointer Dereference condition. The core issue lies in the fillData() function within the Wazuh codebase, where the implementation assumes that input values will always be non-NULL. When a NULL value is passed to os_strdup(), the function attempts to operate on invalid memory, resulting in an immediate crash of the analysisd process.

The Wazuh Manager relies on analysisd as a critical component for processing and analyzing security events from connected agents. When this daemon crashes, the entire security monitoring pipeline becomes unavailable, creating a significant gap in threat detection and response capabilities. This is particularly concerning in enterprise environments where continuous monitoring is essential.

Root Cause

The root cause is improper input validation in the fillData() function. The function directly passes values to os_strdup() without first validating that the value is not NULL. The os_strdup() function, which duplicates a string in memory, cannot handle NULL pointers and will cause a crash when attempting to read from an invalid memory location. This is a classic defensive programming oversight where boundary conditions were not properly handled.

Attack Vector

The attack vector requires a compromised or malicious agent that has established a connection to the Wazuh manager. The attacker must craft a specially formatted message containing NULL values in fields that are subsequently processed by the fillData() function. When the Wazuh manager receives and processes this malformed message, the analysisd daemon attempts to duplicate the NULL value, triggering the crash.

The vulnerability is network-accessible, meaning any agent with network connectivity to the Wazuh manager can potentially exploit this issue. The attack does not require authentication beyond what is needed for agent communication, and the complexity of exploitation is relatively low once an attacker has agent-level access to the environment.

Detection Methods for CVE-2025-62785

Indicators of Compromise

• Unexpected crashes or restarts of the analysisd daemon on Wazuh managers
• Core dump files associated with analysisd process indicating NULL pointer access
• Unusual or malformed messages in Wazuh agent communication logs
• Agent connections from unexpected IP addresses or compromised hosts

Detection Strategies

• Monitor analysisd process stability and implement alerting for unexpected process terminations
• Review Wazuh manager logs for malformed agent messages or protocol violations
• Implement network monitoring to detect unusual patterns in agent-to-manager communications
• Deploy endpoint detection and response (EDR) solutions on agent hosts to identify compromised agents

Monitoring Recommendations

• Configure process monitoring to alert on analysisd crashes with automatic notification to security teams
• Implement log aggregation for Wazuh manager components to centralize crash analysis
• Monitor system resources on Wazuh manager hosts for signs of repeated crash-restart cycles
• Review agent enrollment and authentication logs for unauthorized agent connections

How to Mitigate CVE-2025-62785

Immediate Actions Required

• Upgrade Wazuh to version 4.10.2 or later, which contains the fix for this vulnerability
• Review connected agents for signs of compromise before upgrading
• Implement network segmentation to limit which hosts can communicate with the Wazuh manager
• Enable enhanced logging on the Wazuh manager to assist with forensic analysis if exploitation is suspected

Patch Information

Wazuh has released version 4.10.2 which addresses this vulnerability. The fix adds proper NULL value checking in the fillData() function before calling os_strdup(). The specific commit implementing this fix is available in the GitHub Commit Update. Additional details about this vulnerability can be found in the GitHub Security Advisory GHSA-mqpq-pcxc-8259.

Workarounds

• Implement strict network access controls to limit agent connectivity to trusted hosts only
• Deploy intrusion detection rules to identify malformed agent messages before they reach the manager
• Configure automatic service restart for analysisd to minimize downtime if exploitation occurs
• Consider isolating critical Wazuh manager infrastructure behind additional security controls while awaiting patching

# Configuration example
# Network firewall rule to restrict agent connections to known hosts
iptables -A INPUT -p tcp --dport 1514 -s trusted_agent_network/24 -j ACCEPT
iptables -A INPUT -p tcp --dport 1514 -j DROP

# Enable process monitoring for analysisd
systemctl enable wazuh-manager
echo "Respawn=always" >> /etc/systemd/system/wazuh-manager.service.d/override.conf
systemctl daemon-reload