Privilege escalation in Microsoft SMB

1) Input validation error

EUVDB-ID: #VU18220

Risk: Low

CVSSv4.0: 5.9 [CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:U/U:Clear]

CVE-ID: CVE-2019-0786

CWE-ID: CWE-20 - Improper input validation

Exploit availability: No

Description

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

The vulnerability exists due to an error within the Microsoft Server Message Block (SMB) Server when processing files. A local user can create a specially crafted file and open it over the SMB protocol on the same machine.

Mitigation

Install updates from vendor's website.

Vulnerable software versions

Windows: 10 1709 10.0.16299.19 - 10 1809 10.0.17763.1

Windows Server: 2019 10.0.17763.1 - 2019 1803

CPE2.3

• cpe:2.3:o:microsoft:windows:10_1709:10.0.16299.19:*:*:*:*:*:*
• cpe:2.3:o:microsoft:windows:10_1803:10.0.17134.48:*:*:*:*:*:*
• cpe:2.3:o:microsoft:windows:10_1809:10.0.17763.1:*:*:*:*:*:*
• cpe:2.3:o:microsoft:windows_server:2019:10.0.17763.1:*:*:*:*:*:*
• cpe:2.3:o:microsoft:windows_server:2019_1709:*:*:*:*:*:*:*
• cpe:2.3:o:microsoft:windows_server:2019_1803:*:*:*:*:*:*:*

External links

https://portal.msrc.microsoft.com/en-US/security-guidance/advisory/CVE-2019-0786

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.