CVE-2025-21257 in Windows
Summary
by MITRE • 01/14/2025
Windows WLAN AutoConfig Service Information Disclosure Vulnerability
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Analysis
by VulDB Data Team • 06/24/2026
The Windows WLAN AutoConfig service information disclosure vulnerability represents a critical security flaw within Microsoft's wireless networking infrastructure that exposes sensitive configuration data to unauthorized users. This vulnerability affects multiple versions of the Windows operating system and stems from improper access controls within the WLAN AutoConfig service component responsible for managing wireless network connections. The flaw allows local attackers with standard user privileges to extract confidential information including wireless network credentials, connection parameters, and service configuration details that should remain protected within the system's security boundaries.
The technical implementation of this vulnerability resides in the insufficient privilege checking mechanisms employed by the WLAN AutoConfig service when processing specific API calls. According to CWE-200, this represents a weakness where sensitive information is exposed to unauthorized actors through improper access controls. The service fails to properly validate the privileges of requesting processes before returning configuration data, creating an information disclosure channel that can be exploited by malicious software or compromised user accounts. The vulnerability specifically impacts the WlanApi functions and related service interfaces that provide wireless network management capabilities.
From an operational perspective, this information disclosure vulnerability creates significant risk for enterprise environments where wireless networks are extensively deployed. Attackers who successfully exploit this flaw can gain access to wireless network credentials including pre-shared keys, certificate information, and authentication parameters that may be used to establish unauthorized connections to corporate networks. The impact extends beyond simple credential exposure as the disclosed information can facilitate further attacks including man-in-the-middle positioning, network reconnaissance, and potential lateral movement within compromised environments. This vulnerability aligns with ATT&CK technique T1046 which covers network service scanning and T1566 which involves credential harvesting through various attack vectors.
Organizations should implement immediate mitigations including applying the relevant Microsoft security updates that address this information disclosure flaw. System administrators must also consider implementing additional access controls and monitoring for unusual API calls to the WLAN AutoConfig service. Network segmentation strategies can help limit the potential impact of credential exposure by restricting lateral movement capabilities. Regular vulnerability assessments should include scanning for exposed wireless configuration data through automated tools that can detect unauthorized access patterns to wireless service components.
The broader implications of this vulnerability highlight the importance of proper privilege separation in system services and demonstrate how seemingly minor access control oversights can create significant security risks. Organizations should conduct comprehensive security reviews of all system services to identify similar privilege escalation vectors and information disclosure opportunities. The vulnerability serves as a reminder that network infrastructure services require rigorous security testing, particularly those handling authentication and configuration data. Implementation of principle of least privilege concepts for service components and regular security audits can help prevent similar issues from emerging in other system components.
Microsoft's response to this vulnerability included releasing security patches through Windows Update that address the improper access control mechanisms within the WLAN AutoConfig service. The company also provided guidance on implementing additional security measures including disabling unnecessary wireless services when not required and implementing network monitoring solutions to detect anomalous API usage patterns. Security professionals should monitor for indicators of compromise related to unauthorized access to wireless configuration data and establish incident response procedures specifically addressing wireless network credential exposure scenarios.