External Control of File Name in Microsoft SQL Server

Executive Summary

CVE-2026-55002 is a vulnerability in Microsoft SQL Server that involves external control of a file name or path. This flaw allows an authorized attacker with local access to elevate their privileges on the system. Essentially, the attacker can manipulate file paths or names in a way that grants them higher-level permissions than they should have.

The vulnerability is classified as an elevation of privilege (EoP) issue, meaning it does not directly allow remote code execution or data theft but enables an attacker to gain more control over the affected system.

Useful 0 Not Useful 0

Detection Guidance

The provided context does not include specific detection methods or commands for identifying this vulnerability on a network or system. Detection may require checking SQL Server configurations, file permissions, or logs for unusual file path manipulations by authorized users.

Microsoft may provide detection guidance or tools in their official update guide or security advisories. Refer to the linked resource for potential updates on detection methods.

Useful 0 Not Useful 0

Impact Analysis

If you are using an affected version of Microsoft SQL Server, this vulnerability could have several impacts:

• An attacker with local access and low privileges could exploit this flaw to gain administrative or higher-level access to the SQL Server or the underlying operating system.
• Once elevated, the attacker could perform actions such as installing malicious software, modifying or deleting data, or creating new accounts with full privileges.
• This could lead to data breaches, unauthorized access to sensitive information, or disruption of services relying on the SQL Server.

The CVSS base score of 7.8 indicates a high severity, meaning the impact is significant but requires local access and some level of existing authorization.

Useful 0 Not Useful 0

Compliance Impact

This vulnerability could affect compliance with several standards and regulations, depending on the data and systems involved:

• GDPR (General Data Protection Regulation): If the SQL Server stores or processes personal data of EU citizens, an attacker exploiting this vulnerability could gain unauthorized access to that data. This could result in a data breach, triggering GDPR's reporting requirements and potential fines for failing to protect personal data adequately.
• HIPAA (Health Insurance Portability and Accountability Act): If the SQL Server handles protected health information (PHI), an elevation of privilege could lead to unauthorized access or disclosure of PHI. This would violate HIPAA's security and privacy rules, potentially resulting in penalties.
• Other standards like PCI DSS (Payment Card Industry Data Security Standard) could also be impacted if the SQL Server processes payment card data. Unauthorized access could lead to non-compliance and associated consequences.

Organizations should assess whether their SQL Server instances are affected and apply patches or mitigations promptly to avoid compliance risks.

Useful 0 Not Useful 0

Mitigation Strategies

The provided context does not specify immediate mitigation steps for this vulnerability. However, general best practices for mitigating privilege escalation vulnerabilities in SQL Server may include:

• Apply the latest security updates or patches provided by Microsoft for SQL Server as soon as they are available.
• Restrict access to SQL Server to only authorized users and limit privileges to the minimum required for their roles.
• Monitor and audit SQL Server logs for suspicious activity, such as unauthorized file path manipulations.
• Review and enforce strict file and directory permissions to prevent unauthorized modifications.

For specific mitigation steps, consult the official Microsoft security advisory or update guide linked in the resources.

Useful 0 Not Useful 0