Privilege escalation in Microsoft Windows

Published: 2020-11-26

Risk	Low
Patch available	NO
Number of vulnerabilities	1
CVE-ID	N/A
CWE-ID	CWE-264
Exploitation vector	Local
Public exploit	Public exploit code for vulnerability #1 is available.
Vulnerable software Subscribe	Windows Operating systems & Components / Operating system Windows Server Operating systems & Components / Operating system
Vendor	Microsoft

Security Bulletin

This security bulletin contains one low risk vulnerability.

1) Security restrictions bypass

EUVDB-ID: #VU48660

Risk: Low

CVSSv3.1: 8.1 [CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H/E:U/RL:U/RC:C]

CVE-ID: N/A

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 incorrect permissions set for two registry keys for the RPC Endpoint Mapper and DNSCache services. A local user can modify keys a leverage behavior of other system services to load a malicious DLL and execute arbitrary code with SYSTEM privileges.

Affected registry keys are:

HKLMSYSTEMCurrentControlSetServicesRpcEptMapper
HKLMSYSTEMCurrentControlSetServicesDnscache

Mitigation

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

As a remediation, change permissions on the registry keys and disable access to these keys for unprivileged users.

Vulnerable software versions

Windows: 7 - 7 SP1

Windows Server: 2008 - 2008 SP2

External links

http://itm4n.github.io/windows-registry-rpceptmapper-eop/

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.