Zerologon: Patching Netlogon Elevation of Privilege Vulnerability (CVE-2020-1472) using SanerNow

Overview:

Microsoft team has patched a critical Elevation of Privilege vulnerability in the Netlogon Remote Protocol of the Windows server. CVE identifier CVE-2020-1472 has been assigned to this vulnerability. This vulnerability dubbed as Zerologon, has received the highest severity score of 10.0. Successful exploitation of this vulnerability allows an unauthenticated attacker to gain the Domain Admin privileges by using the domain controller credentials.

CVSS v3.0 Severity and Metrics:
Base Score: 10.0 CRITICAL

CVSS v2.0 Severity and Metrics:
Base Score: 9.3 CRITICAL

Affected software:

• Microsoft Windows Server 2019
• Microsoft Windows Server 2016
• Microsoft Windows Server 2012
• Microsoft Windows Server 2012 R2
• Microsoft Windows Server 2008 R2 Service Pack 1

Solution:

To address this vulnerability, the vendor has released security patches. For more information, please refer to our blog

Use SanerNow platform to apply this critical patch quickly across the organization as shown below.

SanerNow: Vulnerability detection and patching of Zerologon Vulnerability:

1. Login to SanerNow platform

2. Switch to the account/site specific view and Go to 'VM tool'

3. If your Windows Operating System is vulnerable, Saner lists the CVE’s CVE-2020-1472 in 'Top Vulnerabilities' or 'Recently Discovered Vulnerabilities' as shown in the below diagram

4. Search for this vulnerability in VM tool. If you are affected, apply the patch through PM -> Missing Patches

5. Select 'Groups/Devices' in the 'Asset Source' section and click 'Apply'.

6. Select the 'Windows OS' product from the 'Asset' section as shown in the below diagram.

7. Select 'Apply Selected Patches' at the rightmost corner. This will prompt for 'Creating Patching Task'. Fill in 'Task Name' and 'Remediation Schedule' as per your preference and click on 'Apply Selected Patches' as shown below,

8. Remediation job will be created, which will fix the vulnerability by upgrading the operating system and making the system immune to Zerologon vulnerability.

9. Once remediation is done, the Saner agent automatically scans again and upload the result to SanerNow as shown below,