Privilege escalation in Microsoft Defender

1) Permissions, Privileges, and Access Controls

EUVDB-ID: #VU26846

Risk: Medium

CVSSv3.1: 4.8 [CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H/E:U/RL:O/RC:C]

CVE-ID: CVE-2020-1002

CWE-ID: CWE-264 - Permissions, Privileges, and Access Controls

Exploit availability: No

Description

The vulnerability allows a local user to escalate privileges on the system.

The vulnerability exists due to the MpSigStub.exe for Defender allows file deletion in arbitrary locations. A local user can run a specially crafted command and delete protected files on an affected system once MpSigStub.exe ran again.

Mitigation

Cybersecurity Help is currently unaware of any official solution to address this vulnerability..

Vulnerable software versions

Microsoft Forefront Endpoint Protection: 2010

Microsoft Security Essentials: All versions

Windows Defender: for Windows RT 8.1 - for Windows 10, Windows 10 1511, Windows 10 1607, Windows Server 2016, Windows 10 1703

CPE2.3

• cpe:2.3:a:microsoft:microsoft_forefront_endpoint_protection:2010:*:*:*:*:*:*:
• cpe:2.3:a:microsoft:microsoft_security_essentials:*:*:*:*:*:*:*:
• cpe:2.3:a:microsoft:windows_defender:for Windows RT 8.1:*:*:*:*:*:*:
• cpe:2.3:a:microsoft:windows_defender:on Windows Server 2008:*:*:*:*:*:*:
• cpe:2.3:a:microsoft:windows_defender:on Windows Server 2012:*:*:*:*:*:*:

External links

http://portal.msrc.microsoft.com/en-US/security-guidance/advisory/CVE-2020-1002

Q & A

Can this vulnerability be exploited remotely?

No. This vulnerability can be exploited locally. The attacker should have authentication credentials and successfully authenticate on the system.

Is there known malware, which exploits this vulnerability?

No. We are not aware of malware exploiting this vulnerability.