Key Information Summary Vulnerability Overview Title: Microsoft Windows Installer Service Directory Junction Information Disclosure Vulnerability Identifiers: - ZDI: ZDI-21-1103 - ZDI-CAN: ZDI-CAN-13768 - CVE: CVE-2021-36962 CVSS Score: 5.5 - Vector: AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N Affected Information Vendor: Microsoft Product: Windows Vulnerability Details Description: This vulnerability allows a local attacker to disclose sensitive information from an affected Microsoft Windows installation. The attacker must first gain the ability to execute low-privileged code on the target system in order to exploit this vulnerability. By creating a directory junction within the Windows Installer Service, the attacker can abuse the service to disclose the contents of arbitrary files. Attack Scenario: The attacker can leverage this vulnerability to disclose information in the context of SYSTEM. Updates and Patches Microsoft has released an update: For details on the fix, see: https://msrc.microsoft.com/update-guide/vulnerability/CVE-2021-36962 Disclosure Timeline 2021-06-04: Vulnerability reported to vendor 2021-09-16: Coordinated public disclosure 2021-09-20: Update announcement Discoverer Discoverer: Abdelhamid Naceri