CVE-2026-5382: runZero Platform Auth Bypass Vulnerability

CVE-2026-5382 Overview

An incorrect authorization vulnerability has been identified in the runZero Platform that could expose records outside of the authorized organization scope through the MCP (Multi-Cloud Platform) endpoints. This authorization bypass flaw is classified as CWE-863: Incorrect Authorization and could allow authenticated users with high privileges to access sensitive data belonging to other organizations within multi-tenant deployments.

Critical Impact

Authenticated users with high privileges could potentially access records from organizations outside their authorized scope through improperly secured MCP endpoints, leading to cross-tenant information disclosure.

Affected Products

• runZero Platform versions prior to 4.0.260206.0

Discovery Timeline

• 2026-04-07 - CVE CVE-2026-5382 published to NVD
• 2026-04-08 - Last updated in NVD database

Technical Details for CVE-2026-5382

Vulnerability Analysis

This vulnerability stems from an incorrect authorization implementation in the runZero Platform's MCP endpoints. The flaw allows authenticated users with elevated privileges to bypass organization scope restrictions, potentially accessing records belonging to other organizations in multi-tenant environments.

The attack requires network access and high privileges to exploit, with high complexity making successful exploitation more difficult. However, the changed scope indicates that the vulnerability can impact resources beyond the vulnerable component itself. While the confidentiality impact is limited, this type of cross-tenant data exposure is particularly concerning in multi-tenant SaaS environments where data isolation between organizations is paramount.

Root Cause

The vulnerability is caused by improper authorization checks (CWE-863) in the MCP endpoint handlers. The affected endpoints fail to properly validate that the requesting user's organization context matches the organization scope of the requested records, allowing cross-organization data access under specific conditions.

Attack Vector

The attack vector is network-based, requiring an authenticated attacker with high privileges to craft requests to MCP endpoints that bypass organization scope validation. The high attack complexity and privilege requirements reduce the likelihood of widespread exploitation, but targeted attacks against specific high-value data remain a concern.

The vulnerability mechanism involves improper boundary enforcement on API requests to MCP endpoints. When processing certain queries, the authorization layer fails to adequately validate organization scope boundaries, potentially returning records from other organizations. For technical details, refer to the RunZero Advisory CVE-2026-5382.

Detection Methods for CVE-2026-5382

Indicators of Compromise

• Unusual API access patterns to MCP endpoints from privileged accounts
• Cross-organization data access attempts logged in audit trails
• Unexpected record retrievals that don't match the user's organization context
• Anomalous query patterns targeting MCP endpoints with organization parameters

Detection Strategies

• Monitor audit logs for MCP endpoint access patterns that cross organization boundaries
• Implement alerting on API requests returning data outside the authenticated user's organization scope
• Review privileged account activity for unusual MCP endpoint query patterns
• Enable verbose logging on MCP endpoints to capture organization context validation events

Monitoring Recommendations

• Enable enhanced logging for all MCP endpoint transactions in the runZero Platform
• Configure SIEM rules to detect cross-tenant access patterns in API logs
• Regularly audit privileged user activity and API access logs for anomalies
• Implement real-time alerting for organization boundary violations

How to Mitigate CVE-2026-5382

Immediate Actions Required

• Upgrade runZero Platform to version 4.0.260206.0 or later immediately
• Review audit logs for any historical cross-organization data access attempts
• Audit privileged user accounts and their access patterns to MCP endpoints
• Verify organization boundary configurations in multi-tenant deployments

Patch Information

runZero has addressed this vulnerability in version 4.0.260206.0 of the runZero Platform. Organizations should update to this version or later to remediate the authorization bypass issue. Detailed release information is available in the RunZero Release Notes.

Workarounds

• Restrict access to MCP endpoints to only essential privileged users until patching is complete
• Implement additional network-level access controls to limit MCP endpoint exposure
• Enable enhanced audit logging to monitor for exploitation attempts
• Review and minimize privileged account assignments in multi-tenant environments

# Verify runZero Platform version
runzero version

# Confirm upgrade to patched version (4.0.260206.0 or later)
runzero update --check