CVE-2025-29835: Windows 10 1507 Information Disclosure

CVE-2025-29835 Overview

CVE-2025-29835 is an out-of-bounds read vulnerability in the Windows Routing and Remote Access Service (RRAS) that allows an unauthorized attacker to disclose sensitive information over a network. This vulnerability affects a wide range of Microsoft Windows operating systems, including both client and server editions spanning multiple generations of Windows releases.

The vulnerability exists within the RRAS component, a critical Windows service that enables remote access connectivity and routing functionality. When exploited, an attacker can leverage improper memory boundary validation to read data beyond the intended buffer limits, potentially exposing sensitive information from system memory.

Critical Impact

Successful exploitation enables unauthorized disclosure of sensitive system information over the network without requiring authentication, potentially exposing credentials, configuration data, or other confidential memory contents.

Affected Products

• Microsoft Windows 10 (versions 1507, 1607, 1809, 21H2, 22H2)
• Microsoft Windows 11 (versions 22H2, 23H2, 24H2)
• Microsoft Windows Server 2008 R2 SP1, 2012, 2012 R2, 2016, 2019, 2022, 2022 23H2, and 2025

Discovery Timeline

• May 13, 2025 - CVE-2025-29835 published to NVD
• May 19, 2025 - Last updated in NVD database

Technical Details for CVE-2025-29835

Vulnerability Analysis

This vulnerability is classified as CWE-125 (Out-of-bounds Read), a memory safety issue that occurs when the RRAS service reads data from a location outside the boundaries of an allocated memory buffer. The flaw resides in how the service processes network requests without properly validating buffer boundaries.

The attack can be conducted remotely over the network and requires user interaction. An attacker does not need prior authentication or special privileges to attempt exploitation. Successful exploitation results in high confidentiality impact, enabling unauthorized access to sensitive information that should be protected within system memory.

Root Cause

The root cause of CVE-2025-29835 lies in insufficient boundary checking within the Windows Routing and Remote Access Service. When processing certain network data, the RRAS component fails to properly validate the length or bounds of input data before reading memory contents. This allows an attacker to craft malicious network requests that cause the service to read beyond the intended buffer boundaries, returning memory contents that may contain sensitive information.

Out-of-bounds read vulnerabilities typically arise when code uses attacker-controlled index values or lengths without proper validation against buffer size limits.

Attack Vector

The attack vector for CVE-2025-29835 is network-based, meaning an attacker can target vulnerable systems remotely. The exploitation requires some form of user interaction, which may involve enticing a user to connect to a malicious server or interact with crafted network content that triggers the vulnerable code path in RRAS.

The attack flow involves:

1. Attacker crafts a malicious network request designed to trigger the out-of-bounds read condition
2. The target user or system interacts with the malicious content, initiating communication with the RRAS service
3. The RRAS service processes the request and reads memory beyond the intended buffer boundaries
4. Sensitive data from adjacent memory regions is disclosed to the attacker over the network

Since no verified proof-of-concept code is publicly available for this vulnerability, technical details regarding specific exploitation methods should be referenced from the Microsoft Security Update Guide.

Detection Methods for CVE-2025-29835

Indicators of Compromise

• Unusual network traffic patterns targeting RRAS ports (typically TCP/IP ports used for VPN and routing services)
• Abnormal RRAS service crashes or unexpected restarts indicating potential exploitation attempts
• Memory access violations or exceptions logged in Windows Event Logs associated with the RRAS service
• Outbound data transfers from systems running RRAS that don't match normal operational patterns

Detection Strategies

• Monitor Windows Event Logs for RRAS-related errors, particularly those indicating memory access violations or service instability
• Implement network intrusion detection rules to identify malformed or suspicious traffic targeting RRAS endpoints
• Deploy endpoint detection and response (EDR) solutions capable of monitoring memory access patterns in critical Windows services
• Utilize SentinelOne's behavioral AI engine to detect anomalous RRAS service behavior indicative of exploitation attempts

Monitoring Recommendations

• Enable detailed logging for the Routing and Remote Access Service and review logs for anomalies
• Configure alerts for unexpected RRAS service restarts or crash events
• Monitor network traffic to and from systems running RRAS for unusual data patterns or volumes
• Implement baseline monitoring for RRAS memory usage to detect potential exploitation artifacts

How to Mitigate CVE-2025-29835

Immediate Actions Required

• Apply the latest Microsoft security updates addressing CVE-2025-29835 immediately on all affected systems
• Prioritize patching on internet-facing servers and systems where RRAS is actively used for remote access or routing
• Conduct an inventory of all Windows systems running RRAS to ensure comprehensive patch coverage
• Consider temporarily disabling RRAS on non-essential systems until patches can be applied

Patch Information

Microsoft has released security updates to address this vulnerability as part of their regular security update process. Administrators should consult the Microsoft Security Update Guide for CVE-2025-29835 for specific patch information and download links for each affected Windows version.

The patches address the out-of-bounds read condition by implementing proper boundary validation when the RRAS service processes network data, preventing unauthorized memory disclosure.

Workarounds

• Disable the Routing and Remote Access Service on systems where it is not required for business operations
• Implement network segmentation to limit exposure of RRAS-enabled systems to untrusted networks
• Use firewall rules to restrict network access to RRAS services from trusted IP addresses only
• Consider deploying a VPN alternative or network access solution while awaiting patch deployment

# Disable RRAS service if not required
sc stop RemoteAccess
sc config RemoteAccess start= disabled

# Verify RRAS service status
sc query RemoteAccess