CVE-2025-6723: Chef InSpec Privilege Escalation Flaw

CVE-2025-6723 Overview

Chef InSpec up to version 5.23 creates named pipes with overly permissive default Windows access controls. A local attacker may interfere with the pipe connection process and exploit the insufficient access restrictions to assume the InSpec execution context, potentially resulting in elevated privileges or operational disruption.

This vulnerability represents a significant security risk in Windows environments where Chef InSpec is deployed for compliance automation and infrastructure testing, as named pipe security is critical for inter-process communication integrity.

Critical Impact

Local attackers can exploit insecure named pipe permissions to hijack the InSpec execution context, potentially achieving privilege escalation or causing operational disruption in compliance automation workflows.

Affected Products

• Chef InSpec through version 5.23
• Windows-based systems running vulnerable Chef InSpec versions
• Infrastructure automation environments using InSpec for compliance testing

Discovery Timeline

• 2026-01-30 - CVE CVE-2025-6723 published to NVD
• 2026-02-04 - Last updated in NVD database

Technical Details for CVE-2025-6723

Vulnerability Analysis

This vulnerability falls under CWE-269 (Improper Privilege Management) and affects the named pipe implementation in Chef InSpec on Windows systems. Named pipes are a mechanism for inter-process communication (IPC) on Windows, and when created with overly permissive access controls, they become susceptible to hijacking by local attackers.

The core issue stems from Chef InSpec creating named pipes without properly restricting which users or processes can interact with them. This allows a local attacker with low privileges to connect to or manipulate the pipe, potentially intercepting communications or impersonating the InSpec process context.

The attack requires local access and presents some complexity due to timing considerations around the pipe connection process. However, successful exploitation can lead to high integrity impact, allowing attackers to manipulate compliance data or escalate their privileges within the system.

Root Cause

The root cause is the use of default or overly permissive Windows access control lists (ACLs) when creating named pipes for inter-process communication. Chef InSpec fails to properly restrict pipe access to only authorized processes and users, creating an opportunity for local privilege escalation.

When a named pipe is created without explicit security descriptors limiting access, Windows applies default permissions that may allow any authenticated user to connect. This fundamental access control oversight enables the attack vector.

Attack Vector

The attack vector is local, requiring the attacker to have an existing foothold on the target system. The exploitation process involves:

1. Reconnaissance - The attacker identifies InSpec processes and their associated named pipes on the Windows system
2. Timing - The attacker monitors for InSpec execution and pipe creation events
3. Interception - Due to insufficient access controls, the attacker connects to or creates a competing named pipe before the legitimate client
4. Context Assumption - The attacker assumes the InSpec execution context, potentially gaining elevated privileges or the ability to manipulate compliance operations

The vulnerability mechanism centers on the improper access control configuration during named pipe creation. When Chef InSpec establishes a named pipe for inter-process communication, the security descriptor applied to the pipe object does not adequately restrict which principals can connect. This allows a local attacker to race the legitimate connection and potentially hijack the communication channel. For detailed technical specifications, refer to the Chef InSpec Documentation.

Detection Methods for CVE-2025-6723

Indicators of Compromise

• Unexpected processes connecting to Chef InSpec named pipes
• Anomalous named pipe creation events with permissive security descriptors
• Suspicious local user activity correlating with InSpec execution times
• Unexplained privilege escalation following compliance scan operations

Detection Strategies

• Monitor Windows Security Event logs for named pipe access events (Event ID 5145 for network share access, Event ID 4656 for handle requests)
• Implement Sysmon logging to capture pipe connection events with detailed process information
• Configure endpoint detection rules to alert on non-standard processes accessing InSpec-related named pipes
• Deploy behavioral analytics to identify timing-based attacks on IPC mechanisms

Monitoring Recommendations

• Enable detailed audit logging for object access on Windows endpoints running Chef InSpec
• Implement real-time monitoring of named pipe creation and connection events
• Establish baseline behavior for InSpec execution patterns to detect anomalies
• Configure alerts for privilege escalation events following InSpec process activity

How to Mitigate CVE-2025-6723

Immediate Actions Required

• Identify all systems running Chef InSpec version 5.23 or earlier
• Assess the risk level for each deployment based on local access exposure
• Prioritize patching for systems in multi-user environments or those accessible to less-trusted users
• Implement additional access controls and monitoring while awaiting patches

Patch Information

Organizations should update Chef InSpec to a version newer than 5.23 that addresses the named pipe access control issue. Consult the Chef InSpec Documentation for the latest security updates and release information. Verify patch availability through official Chef channels and test updates in non-production environments before deployment.

Workarounds

• Restrict local access to systems running Chef InSpec to only trusted administrators
• Implement Windows security policies to limit named pipe creation and access privileges
• Run InSpec operations on isolated or single-user systems where possible
• Consider containerized or sandboxed execution environments to limit the attack surface

If immediate patching is not possible, administrators should implement compensating controls by restricting local logon rights and applying the principle of least privilege to minimize the risk of exploitation. Additionally, enhanced monitoring of named pipe activity can provide early warning of attempted attacks.