BaseFortify

Executive Summary

CVE-2026-34346 is a vulnerability in the Windows Ancillary Function Driver for WinSock. It involves the cleartext transmission of sensitive information, meaning data is sent or processed in an unencrypted form.

An authorized attacker with local access to the system can exploit this flaw to disclose sensitive information. The vulnerability does not require user interaction and is classified as an information disclosure issue.

• Affected component: Windows Ancillary Function Driver for WinSock.
• Attack vector: Local (AV:L), meaning the attacker must have access to the system.
• Privileges required: Low (PR:L), indicating the attacker needs some level of authorization.
• Impact: High confidentiality impact (C:H), as sensitive data can be exposed.

Useful 0 Not Useful 0

Impact Analysis

This vulnerability can impact you if you are using a system with the affected Windows Ancillary Function Driver for WinSock.

• An attacker with local access to your system could exploit this flaw to access sensitive information transmitted in cleartext.
• The disclosed information could include credentials, personal data, or other confidential details, depending on the applications using the affected driver.
• Since the vulnerability has a high confidentiality impact, the exposure of sensitive data could lead to further attacks or unauthorized access to other systems.

Useful 0 Not Useful 0

Compliance Impact

This vulnerability could affect compliance with several standards and regulations, depending on the nature of the data exposed.

• GDPR: If the disclosed information includes personal data of EU citizens, this could violate GDPR requirements for data protection and confidentiality. Organizations may face penalties for failing to secure personal data.
• HIPAA: If the exposed data includes protected health information (PHI), this could result in a HIPAA violation. Covered entities and business associates must ensure the confidentiality of PHI, and this vulnerability could lead to unauthorized disclosure.
• Other standards: Depending on the industry, this vulnerability could also impact compliance with frameworks like PCI DSS (if payment data is exposed) or other data protection regulations.

Organizations should assess the types of data processed by the affected system and take corrective actions to mitigate the risk of non-compliance.

Useful 0 Not Useful 0

Detection Guidance

The provided context does not include specific detection methods or commands for identifying the cleartext transmission of sensitive information in Windows Ancillary Function Driver for WinSock. Detection may require monitoring local system interactions with the affected driver or using specialized tools to inspect WinSock-related traffic for unencrypted sensitive data.

Since this vulnerability involves local information disclosure, network-based detection may not be applicable. You may need to refer to Microsoft's official guidance or security tools for precise detection steps.

Useful 0 Not Useful 0

Mitigation Strategies

The provided context does not specify immediate mitigation steps for CVE-2026-34346. However, general best practices for addressing such vulnerabilities include:

• Apply the latest security updates or patches provided by Microsoft for Windows Ancillary Function Driver for WinSock.
• Restrict local access to sensitive systems to minimize the risk of exploitation by authorized attackers.
• Monitor Microsoft's official security advisory for specific guidance and updates related to this CVE.

For precise mitigation steps, refer to the official Microsoft update guide linked in Resource 1.

Useful 0 Not Useful 0