CVE-2026-102225 – Windows Text Shaping Remote Code Execution Vulnerability

A critical Remote Code Execution (RCE) vulnerability has been identified in Microsoft Windows Text Shaping, affecting multiple versions of Windows 10, Windows 11, Windows Server, and Microsoft Visual Studio 2026. The vulnerability allows an unauthorized attacker to execute malicious code remotely by convincing a user to open a specially crafted file. The issue involves an out-of-bounds read and a numeric truncation error, potentially allowing attackers to compromise system confidentiality, integrity, and availability. Although Microsoft currently assesses exploitation as less likely, the vulnerability carries a high CVSS score of 8.8 and requires no attacker privileges, making it a significant security concern for organizations.

CVSS SCORE: 8.8

SEVERITY: Critical

Threat

This vulnerability presents a serious security threat because attackers could execute malicious code on affected systems without requiring authentication or elevated privileges.

The attack can be initiated remotely over a network, but successful exploitation requires a user to open a specially crafted malicious file.

Key security risks include:

• Remote Code Execution: Attackers could execute unauthorized code on vulnerable systems.
• Sensitive Data Exposure: Successful exploitation could compromise confidential business information.
• System Compromise: Attackers could potentially modify files, disrupt applications, or interfere with system operations.
• Business Disruption: Compromised systems could become unavailable, affecting employee productivity and critical services.
• Low Attack Complexity: The vulnerability is rated as requiring low attack complexity, increasing concern about potential exploitation.

The vulnerability has a high impact rating across confidentiality, integrity, and availability.

Exploits

Microsoft has classified this vulnerability as Exploitation Less Likely.

Current exploitation information indicates:

• Actively Exploited: No
• Publicly Disclosed: No
• Exploit Code Maturity: Unproven
• Zero-Day Exploitation: No known exploitation is reported.
• Public Proof-of-Concept (PoC): The existence of publicly available PoC exploit code is not confirmed.

Although there is no reported active exploitation, the vulnerability remains critical because successful exploitation could allow remote code execution.

Attackers do not require existing privileges on the affected system. However, they must convince a user to open a specially crafted file.

Technical Summary

CVE-2026-102225 is a critical Remote Code Execution vulnerability affecting the Windows Text Shaping functionality.

The vulnerability is associated with two security weaknesses:

1. Out-of-Bounds Read (CWE-125)

An out-of-bounds read occurs when software attempts to access memory outside the boundaries of an allocated memory region.

In this vulnerability, improper memory access within Windows Text Shaping could contribute to conditions that allow remote code execution.

2. Numeric Truncation Error (CWE-197)

A numeric truncation error occurs when a numeric value is converted or processed in a way that causes information to be lost.

Such errors can result in incorrect calculations or unexpected application behavior.

The vulnerability involves these two weaknesses, although the exact relationship between them and the complete exploitation mechanism is not specified.

Attack Mechanism:

An attacker can prepare a specially crafted malicious file designed to trigger the vulnerability.

The attacker must then convince a targeted user to open that file on an affected system.

When the vulnerable Windows Text Shaping functionality processes the malicious content, the vulnerability could be triggered, potentially allowing the attacker to execute unauthorized code.

The attack has the following characteristics:

• Attack Vector: Network
• Attack Complexity: Low
• Privileges Required: None
• User Interaction: Required
• Scope: Unchanged
• Confidentiality Impact: High
• Integrity Impact: High
• Availability Impact: High

Successful exploitation could compromise sensitive information, allow unauthorized modification of system resources, or disrupt affected systems.

Microsoft has released an official security fix to address the vulnerability.

Exploitability

The vulnerability affects multiple Microsoft products, including:

• Windows 10: Versions 1607, 1809, 21H2, and 22H2.
• Windows 11: Versions 23H2, 24H2, 25H2, and 26H1.
• Windows Server: 2012, 2012 R2, 2016, 2019, 2022, and 2025, including Server Core installations.
• Microsoft Visual Studio: 2026 version 18.10.

Affected Windows architectures include 32-bit, x64, and ARM64, depending on the product version.

Exploitation Requirements:

An attacker does not need authentication or existing system privileges.

However, exploitation requires a user to open a specially crafted malicious file.

Microsoft currently considers exploitation less likely.

Business Impact

This vulnerability could have significant consequences for organizations operating affected Windows endpoints, servers, and development environments.

Because the vulnerability allows remote code execution, successful exploitation could affect the security and reliability of critical business systems.

1. Unauthorized System Access

Attackers could execute malicious code on vulnerable systems, potentially compromising business applications and system resources.

2. Sensitive Information Exposure

Successful exploitation could expose confidential business information, customer records, or other sensitive data accessible within the compromised environment.

3. Operational Disruption

Compromised systems could experience service interruptions, application failures, or unauthorized changes that affect normal business operations.

4. Financial and Recovery Costs

A successful attack could result in incident response expenses, system restoration costs, operational downtime, and potential financial losses.

5. Increased Enterprise Exposure

The vulnerability affects a broad range of Microsoft products, including workstation operating systems, enterprise servers, and development environments.

Organizations operating multiple affected products may face increased exposure if security updates are delayed.

Business Risk Statement:

“A single malicious file could turn an ordinary user action into a serious security incident, putting business data, system integrity, and critical operations at risk.”

Even without confirmed active exploitation, the combination of critical severity, low attack complexity, and remote code execution makes this vulnerability an important patching priority.

Workaround

Microsoft has not identified any official workarounds or mitigations for this vulnerability.

If immediate patching is not possible, organizations can consider temporary risk-reduction measures:

• Warn users against opening unexpected or untrusted files.
• Restrict access to suspicious attachments and files where practical.
• Monitor endpoints for unusual file execution and suspicious activity.
• Prioritize patching systems that frequently process externally received files.
• Apply the appropriate Microsoft security update as soon as operationally possible.

These measures may reduce exposure but do not eliminate the underlying vulnerability.

Urgency

Critical Priority – Deploy Security Updates Promptly

CVE-2026-102225 should be prioritized for deployment because it is classified as Critical and has a CVSS base score of 8.8.

Although the vulnerability is not publicly disclosed and no active exploitation has been reported, its potential impact remains significant.

Several factors support prompt remediation:

• Critical Severity: Successful exploitation could result in remote code execution.
• No Privileges Required: Attackers do not need existing access to the targeted system.
• Low Attack Complexity: Exploitation does not require complex attack conditions.
• Broad Product Exposure: Multiple Windows desktop, server, and development products are affected.
• High Security Impact: Confidentiality, integrity, and availability could all be severely affected.

Recommended Deployment Action:

IT and security teams should identify affected systems and deploy the applicable Microsoft security updates through their standard patch management process.

Relevant security updates include:

• KB5127648: Windows 11 versions 24H2/25H2 and Visual Studio 2026 version 18.10.
• KB5127646: Windows 11 version 26H1.
• KB5126653: Windows 11 version 23H2.
• KB5126657: Windows 10 versions 21H2/22H2.
• KB5126868: Windows 10 version 1607 and Windows Server 2016.
• KB5126651: Windows 10 version 1809 and Windows Server 2019.
• KB5126835: Windows Server 2012.
• KB5126836: Windows Server 2012 R2.
• KB5126655: Windows Server 2022.
• KB5126646: Windows Server 2025.

A system restart is required after installing the applicable security updates.

No known issues are listed for these updates.

Organizations should validate successful installation and complete any required restarts to ensure remediation.