# Critical BitLocker Vulnerability Exposes Windows Devices to Physical Attacks

*Published July 17, 2026*
*Source: [https://cybersecuritynews.com/windows-bitlocker-0-day-vulnerability-2/](https://cybersecuritynews.com/windows-bitlocker-0-day-vulnerability-2/)*

## Executive Summary

A newly disclosed vulnerability in Windows BitLocker, CVE-2026-50661, allows bypassing of encryption protections when attackers have physical access to devices. Microsoft has released updates to address this vulnerability, urging organizations to apply these fixes and consider additional security measures.

## Article

A critical vulnerability in Windows BitLocker, identified as CVE-2026-50661, has been disclosed and raises concerns for devices relying on Microsoft's encryption solutions. This flaw allows unauthorized attackers with physical access to bypass BitLocker’s encryption, compromising the security of data stored on these devices. The vulnerability, classified as a security feature bypass, is a result of a failure in BitLocker’s protection mechanisms during the encryption workflow. It is important to note that while this vulnerability has been publicly disclosed, there have been no reports of it being actively exploited as of the July 2026 Patch Tuesday release. However, the potential impact remains significant, especially for organizations that depend on BitLocker for protecting data at rest on laptops, branch servers, and cloud-adjacent infrastructure. Microsoft has addressed this vulnerability by releasing security updates on July 14, 2026. These updates cover various versions of Windows 10, Windows 11, and Windows Server, with specific patches like KB5099535 and KB5099539 developed to harden BitLocker's protection. Although Microsoft assesses the likelihood of exploitation as low, the risk is notable for scenarios involving physical access to devices. Administrators are strongly advised to apply these security updates promptly and ensure that BitLocker is correctly configured thereafter. To mitigate future risks, organizations should consider implementing additional security measures such as pre-boot PINs, secure boot enforcement, and hardware-backed key storage. Microsoft acknowledges the efforts of an anonymous researcher for bringing this issue to light and provides further guidance through its support lifecycle documentation and update catalog.