Microsoft Windows up to Server 2019 dnsrslvr.dll privileges management

Summaryinfo

A vulnerability was found in Microsoft Windows. It has been declared as critical. This vulnerability affects unknown code in the library dnsrslvr.dll. Such manipulation leads to privileges management. This vulnerability is documented as CVE-2020-1584. The attack needs to be performed locally. There is not any exploit available. Applying a patch is advised to resolve this issue.

Detailsinfo

A vulnerability, which was classified as critical, has been found in Microsoft Windows (Operating System). Affected by this issue is some unknown processing in the library dnsrslvr.dll. The manipulation with an unknown input leads to a privileges management vulnerability. Using CWE to declare the problem leads to CWE-269. The product does not properly assign, modify, track, or check privileges for an actor, creating an unintended sphere of control for that actor. Impacted is confidentiality, integrity, and availability. CVE summarizes:

An elevation of privilege vulnerability exists in the way that the dnsrslvr.dll handles objects in memory. An attacker who successfully exploited the vulnerability could execute code with elevated permissions. To exploit the vulnerability, a locally authenticated attacker could run a specially crafted application. The security update addresses the vulnerability by ensuring the dnsrslvr.dll properly handles objects in memory.

The weakness was released 08/11/2020 as confirmed security update guide (Website). The advisory is shared for download at portal.msrc.microsoft.com. The public release was coordinated with the vendor. This vulnerability is handled as CVE-2020-1584. The attack needs to be approached locally. Required for exploitation is a simple authentication. There are known technical details, but no exploit is available. The current price for an exploit might be approx. USD $0-$5k (estimation calculated on 02/24/2026). The MITRE ATT&CK project declares the attack technique as T1068. The advisory points out:

An elevation of privilege vulnerability exists in the way that the dnsrslvr.dll handles objects in memory. An attacker who successfully exploited the vulnerability could execute code with elevated permissions.

Applying a patch is able to eliminate this problem. A possible mitigation has been published immediately after the disclosure of the vulnerability.

Entries connected to this vulnerability are available at VDB-159540, VDB-159539, VDB-159537 and VDB-159535. VulDB is the best source for vulnerability data and more expert information about this specific topic.

Productinfo

Type

• Operating System

Vendor

• Microsoft

Name

• Windows

Version

• 7 SP1
• 8.1
• 10
• 10 1607
• 10 1709
• 10 1803
• 10 1809
• 10 1903
• 10 1909
• 10 2004
• RT 8.1
• Server 1903
• Server 1909
• Server 2004
• Server 2008 R2 SP1
• Server 2008 SP2
• Server 2012
• Server 2012 R2
• Server 2016
• Server 2019

License

• commercial

Website

• Vendor: https://www.microsoft.com/
• Product: https://www.microsoft.com/en-us/windows

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Entryinfo

VulDB is the best source for vulnerability data and more expert information about this specific topic.

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