CVE-2026-49180 in Windows
Summary
by MITRE • 07/14/2026
Improper link resolution before file access ('link following') in Universal Plug and Play (upnp.dll) allows an authorized attacker to disclose information locally.
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Analysis
by VulDB Data Team • 07/15/2026
This vulnerability represents a critical security flaw in the Universal Plug and Play implementation within Windows operating systems, specifically affecting the upnp.dll component that handles network device discovery and communication protocols. The issue stems from improper handling of symbolic links and file path resolution mechanisms during UPnP operations, creating a privilege escalation vector that allows authenticated attackers to bypass normal access controls and potentially disclose sensitive local information. The vulnerability exists because the system fails to properly validate or sanitize file paths when processing UPnP requests, enabling malicious actors to manipulate symbolic link resolution processes to access files outside of intended boundaries. This weakness aligns with CWE-367, which specifically addresses time-of-check to time-of-use (TOCTOU) vulnerabilities and improper link resolution issues that can lead to information disclosure and privilege escalation scenarios.
The technical exploitation of this vulnerability requires an authenticated attacker with local access to a target system running affected UPnP services. Attackers can leverage the flawed link resolution mechanism to traverse file system boundaries, potentially accessing sensitive files such as configuration data, user credentials stored in memory, or other privileged information that should normally be restricted. The attack typically involves crafting specific UPnP requests that trigger the vulnerable path resolution logic within upnp.dll, allowing the attacker to follow symbolic links to unintended locations and retrieve information that would otherwise be protected by normal file access controls. This type of vulnerability demonstrates a classic flaw in Windows kernel-mode drivers where insufficient input validation leads to unauthorized information disclosure.
From an operational impact perspective, this vulnerability creates significant security risks for enterprise environments where UPnP services are enabled, as it allows local attackers with basic user privileges to potentially escalate their access and obtain sensitive system information. The attack surface is particularly concerning because UPnP functionality is often enabled by default on many Windows systems, especially in consumer and enterprise networks where device discovery and automatic configuration are commonly used. Organizations may experience unauthorized information disclosure, potential credential harvesting, and increased risk of subsequent attacks that could leverage the disclosed information to gain further system access or escalate privileges. The vulnerability's impact extends beyond simple information disclosure as it can serve as a stepping stone for more sophisticated attacks targeting system integrity and confidentiality.
Mitigation strategies should focus on both immediate operational fixes and long-term architectural improvements. Microsoft recommends enabling Windows Defender Application Control policies to restrict execution of untrusted UPnP components, disabling unnecessary UPnP services through Group Policy configurations, and implementing strict network segmentation controls to limit local access to systems with UPnP enabled. Organizations should also consider deploying endpoint detection and response solutions that can monitor for suspicious UPnP activity patterns or anomalous file system access attempts that may indicate exploitation attempts. The vulnerability highlights the importance of proper input validation in system-level components and aligns with ATT&CK technique T1068, which covers local privilege escalation through flawed system services. Network administrators should conduct thorough vulnerability assessments to identify systems running UPnP services and ensure appropriate security controls are in place to prevent exploitation of this class of vulnerabilities.