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CVE-2020-1472

Microsoft Netlogon Privilege Escalation Vulnerability

KEVMEDIUM 5.5EPSS 99.4%

Does this matter?

Known to be exploited in the wild (CISA KEV, CISA remediation deadline 3 May 2022). Treat as an emergency change: patch or isolate now, then hunt for prior compromise.

Description

An elevation of privilege vulnerability exists when an attacker establishes a vulnerable Netlogon secure channel connection to a domain controller, using the Netlogon Remote Protocol (MS-NRPC). An attacker who successfully exploited the vulnerability could run a specially crafted application on a device on the network. To exploit the vulnerability, an unauthenticated attacker would be required to use MS-NRPC to connect to a domain controller to obtain domain administrator access. Microsoft is addressing the vulnerability in a phased two-part rollout. These updates address the vulnerability by modifying how Netlogon handles the usage of Netlogon secure channels. For guidelines on how to manage the changes required for this vulnerability and more information on the phased rollout, see How to manage the changes in Netlogon secure channel connections associated with CVE-2020-1472 (updated September 28, 2020). When the second phase of Windows updates become available in Q1 2021, customers will be notified via a revision to this security vulnerability. If you wish to be notified when these updates are released, we recommend that you register for the security notifications mailer to be alerted of content changes to this advisory. See Microsoft Technical Security Notifications.

CVSS 3.1
5.5 MEDIUMCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N
EPSS
99.39% probability · 100th percentile
CISA KEV
Listed 3 November 2021 · due 3 May 2022 · used in ransomware campaigns
Affected
microsoft/windows server 1903 · microsoft/windows server 1909 · microsoft/windows server 2004 · microsoft/windows server 2008 · microsoft/windows server 2012 · microsoft/windows server 2016 · microsoft/windows server 2019 · microsoft/windows server 20h2 · fedoraproject/fedora · opensuse/leap · canonical/ubuntu linux · synology/directory server · samba/samba · debian/debian linux · oracle/zfs storage appliance kit
Source
secure@microsoft.com

CISA notes

Apply updates per vendor instructions. Reference CISA's ED 20-04 (https://www.cisa.gov/news-events/directives/ed-20-04-mitigate-netlogon-elevation-privilege-vulnerability-august-2020-patch-tuesday) for further guidance and requirements. Note: The due date for addressing this vulnerability aligns with the requirements outlined in ED 20-04. https://nvd.nist.gov/vuln/detail/CVE-2020-1472

References

Source: NVD record, EPSS from FIRST.org, KEV from CISA. Refreshed daily.