CVE-2026-5374: runZero Platform Auth Bypass Vulnerability

CVE-2026-5374 Overview

An authorization bypass vulnerability has been identified in the runZero Platform that allowed MCP (Model Context Protocol) agents to access remediation and asset information from outside of the authorized organization scope. This incorrect authorization issue (CWE-863) could enable privileged attackers to obtain sensitive information about assets and remediation actions belonging to other organizations within multi-tenant deployments.

Critical Impact

MCP agents could access sensitive remediation and asset data across organizational boundaries, potentially exposing confidential security posture information to unauthorized parties.

Affected Products

• runZero Platform versions prior to 4.0.260202.0

Discovery Timeline

• 2026-04-07 - CVE CVE-2026-5374 published to NVD
• 2026-04-08 - Last updated in NVD database

Technical Details for CVE-2026-5374

Vulnerability Analysis

This vulnerability represents an incorrect authorization flaw (CWE-863) in the runZero Platform's MCP agent integration. The issue stems from inadequate boundary enforcement when MCP agents request remediation and asset information, allowing agents to retrieve data that should be restricted to specific organizational scopes.

The network-accessible nature of the vulnerability means an attacker with high privileges could potentially exploit this remotely, though the attack complexity is high. The scope change characteristic indicates that the vulnerability affects resources beyond the vulnerable component itself—specifically, data belonging to other organizations within the platform.

Root Cause

The root cause is an incorrect authorization check in the runZero Platform's MCP agent data access layer. When MCP agents queried for remediation tasks and asset information, the authorization logic failed to properly validate that the requesting agent was authorized to access data within the specified organizational scope. This allowed cross-tenant information disclosure where agents could retrieve sensitive asset and remediation data belonging to organizations outside their authorized access boundaries.

Attack Vector

The vulnerability is exploitable over the network by an attacker with high privileges (such as access to an MCP agent configuration). The attack requires specific conditions to be met, resulting in high complexity:

1. The attacker must have access to configure or control an MCP agent connected to the runZero Platform
2. The attacker must craft requests through the MCP agent targeting remediation or asset endpoints
3. The MCP agent's requests bypass organizational scope validation, returning data from other organizations

While no integrity or availability impact exists, the confidentiality impact is high, particularly in multi-tenant environments where organizations rely on strict data isolation.

Detection Methods for CVE-2026-5374

Indicators of Compromise

• Unusual MCP agent queries retrieving asset or remediation data for organizations outside the agent's configured scope
• Anomalous data access patterns in runZero Platform audit logs showing cross-organization data retrieval
• MCP agent activity logs indicating requests for remediation information beyond authorized boundaries

Detection Strategies

• Review runZero Platform audit logs for MCP agent requests that access resources outside their designated organization scope
• Monitor for abnormal spikes in MCP agent data retrieval volume that could indicate unauthorized enumeration
• Implement alerting on any cross-organizational data access attempts through MCP integrations

Monitoring Recommendations

• Enable comprehensive logging for all MCP agent interactions with the runZero Platform
• Establish baseline behavior for MCP agent queries and alert on deviations
• Regularly audit organization scope configurations and MCP agent permissions

How to Mitigate CVE-2026-5374

Immediate Actions Required

• Upgrade the runZero Platform to version 4.0.260202.0 or later immediately
• Review MCP agent configurations and restrict permissions to minimum required scope
• Audit historical MCP agent activity logs for potential unauthorized data access
• Verify multi-tenant isolation settings are correctly configured

Patch Information

runZero has addressed this vulnerability in version 4.0.260202.0 of the runZero Platform. Organizations should apply this update as soon as possible. Detailed release information is available in the runZero Release Notes. The official security advisory can be found at the runZero Security Advisory for CVE-2026-5374.

Workarounds

• Temporarily disable MCP agent integrations until the patch can be applied
• Implement network-level restrictions to limit MCP agent connectivity
• Review and restrict MCP agent service accounts to minimum necessary privileges
• Enable enhanced logging and monitoring to detect any exploitation attempts before patching