CVE-2026-32085: Windows RPC Information Disclosure Flaw

CVE-2026-32085 Overview

CVE-2026-32085 is an information disclosure vulnerability in Windows Remote Procedure Call (RPC) that allows an authorized attacker to expose sensitive information through local access. The vulnerability is classified under CWE-200 (Exposure of Sensitive Information to an Unauthorized Actor), indicating improper handling of sensitive data within the RPC service.

Windows RPC is a critical interprocess communication mechanism that enables software components to communicate across network boundaries. When exploited, this vulnerability could allow attackers with local access to obtain sensitive system information that should be protected from unauthorized disclosure.

Critical Impact

Local attackers with valid credentials can exploit this vulnerability to disclose sensitive information from the Windows RPC service, potentially exposing confidential system data or user information.

Affected Products

• Windows Remote Procedure Call (RPC) Service
• Microsoft Windows Operating Systems with RPC enabled

Discovery Timeline

• April 14, 2026 - CVE-2026-32085 published to NVD
• April 14, 2026 - Last updated in NVD database

Technical Details for CVE-2026-32085

Vulnerability Analysis

This vulnerability exists within the Windows Remote Procedure Call service and allows information disclosure through local access vectors. The flaw enables an authenticated attacker to access sensitive information that the RPC service fails to properly protect. The vulnerability requires local access and low-privileged authentication, but does not require user interaction to exploit.

The impact is confined to confidentiality, meaning successful exploitation results in unauthorized access to sensitive data without affecting system integrity or availability. The scope remains unchanged, indicating the vulnerable component and impacted component are the same.

Root Cause

The root cause of CVE-2026-32085 lies in improper information exposure handling within the Windows RPC service. The vulnerability stems from CWE-200 (Exposure of Sensitive Information to an Unauthorized Actor), where the RPC service inadvertently makes sensitive information accessible to authenticated users who should not have access to that data.

This type of vulnerability typically occurs when:

• Sensitive data is not properly sanitized before being returned in RPC responses
• Access control checks are insufficient for certain RPC operations
• Memory or data structures containing sensitive information are improperly exposed through RPC interfaces

Attack Vector

The attack vector for CVE-2026-32085 is local, requiring the attacker to have authenticated access to the target system. The exploitation path involves:

1. Initial Access: Attacker gains local access to a Windows system with valid credentials
2. Privilege Context: Exploitation requires only low-level privileges (standard user account)
3. RPC Interaction: Attacker interacts with the vulnerable RPC service endpoint
4. Information Extraction: Sensitive information is disclosed through the improperly protected RPC interface

The vulnerability does not require any user interaction, making it exploitable whenever an authenticated attacker has local access to an affected system. For detailed technical information, refer to the Microsoft CVE-2026-32085 Advisory.

Detection Methods for CVE-2026-32085

Indicators of Compromise

• Unusual RPC service activity from non-administrative user accounts
• Anomalous local process interactions with rpcss.dll or RPC-related system components
• Unexpected information access patterns in Windows Security event logs (Event ID 4656, 4663)
• Suspicious named pipe or ALPC communications targeting RPC endpoints

Detection Strategies

• Monitor Windows Security event logs for unusual RPC endpoint access patterns
• Implement endpoint detection rules for anomalous local RPC service interactions
• Deploy behavioral analysis to detect unauthorized information access attempts from low-privileged accounts
• Use SentinelOne's behavioral AI to identify exploitation attempts targeting Windows RPC services

Monitoring Recommendations

• Enable detailed auditing for Windows RPC service access through Group Policy
• Configure Windows Event Forwarding to centralize RPC-related security events
• Implement SIEM correlation rules to detect patterns consistent with information disclosure attempts
• Monitor for processes making unusual numbers of RPC calls or accessing unexpected RPC interfaces

How to Mitigate CVE-2026-32085

Immediate Actions Required

• Apply the latest Microsoft security updates addressing CVE-2026-32085
• Review and restrict local access privileges to minimize potential exploitation
• Implement network segmentation to limit lateral movement opportunities
• Enable enhanced monitoring on systems where immediate patching is not possible

Patch Information

Microsoft has released security updates to address this vulnerability. System administrators should consult the Microsoft CVE-2026-32085 Advisory for specific patch details and download links. Apply patches through Windows Update, WSUS, or Microsoft Update Catalog based on your organization's patch management infrastructure.

Workarounds

• Restrict local user access to systems running vulnerable RPC services where possible
• Implement application whitelisting to limit which processes can interact with RPC endpoints
• Apply principle of least privilege to minimize the number of accounts with local access
• Consider disabling unnecessary RPC endpoints if they are not required for business operations

# Verify Windows Update status for RPC security patches
wmic qfe list brief /format:table | findstr /i "KB"

# Check RPC service status
sc query rpcss

# Review local security policy for RPC restrictions
secedit /export /cfg current_security_policy.inf