Microsoft · Netlogon
CVE-2020-1472
Netlogon Elevation of Privilege Vulnerability
What it is
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.
CISA: Microsoft's Netlogon Remote Protocol (MS-NRPC) contains a privilege escalation vulnerability when an attacker establishes a vulnerable Netlogon secure channel connection to a domain controller. An attacker who successfully exploits the vulnerability could run a specially crafted application on a device on the network. The vulnerability is also known under the moniker of Zerologon.
What to do
Apply updates per vendor instructions.
Deadline for US federal agencies: May 3, 2022
- Added to the CISA list
- November 3, 2021
- Published
- August 17, 2020
- Severity
- Medium 5.5 CVSS 3.1
- Chance of attacks in the next 30 days (EPSS)
- 99.4% in the top 0.1% of all known vulnerabilities
- Weakness
- CWE-330
- More details
- NVD · CVE.org · CISA
All references (17)
- https://usn.ubuntu.com/4510-1/
- https://usn.ubuntu.com/4510-2/
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/H4OTFBL6YDVF…
- http://lists.opensuse.org/opensuse-security-announce/2020-09/msg00080.html
- http://lists.opensuse.org/opensuse-security-announce/2020-09/msg00086.html
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/TAPQQZZAT4TG…
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/ST6X3A2XXYMG…
- https://usn.ubuntu.com/4559-1/
- https://security.gentoo.org/glsa/202012-24
- https://portal.msrc.microsoft.com/en-US/security-guidance/advisory/CVE-2020-1472
- https://www.kb.cert.org/vuls/id/490028
- http://www.openwall.com/lists/oss-security/2020/09/17/2
- https://lists.debian.org/debian-lts-announce/2020/11/msg00041.html
- https://www.oracle.com/security-alerts/cpuApr2021.html
- http://packetstormsecurity.com/files/159190/Zerologon-Proof-Of-Concept.html
- https://www.synology.com/security/advisory/Synology_SA_20_21
- http://packetstormsecurity.com/files/160127/Zerologon-Netlogon-Privilege-Escalation.html
More exploited flaws from Microsoft
| Added | Vulnerability | Product | Severity | Attack chance |
|---|---|---|---|---|
| Oct 13, 2026 | Command Injection | Windows | High 8.8 | 9.8% |
| Sep 25, 2026 | Code Injection | SharePoint | High 8.8 | 8.2% |
| Sep 8, 2026 | Link Following | Windows | High 7.8 | 0.4% |
| Sep 8, 2026 | Heap-Based Buffer Overflow | Windows | High 7.8 | 0.4% |
| Aug 26, 2026 | Remote Code Execution | SQL Server | High 8.8 | 57% |
| Aug 18, 2026 | Double Free | Internet Key Exchange (IKE) Service Extensions | Critical 9.8 | 77% |
| Aug 18, 2026 | Weak Authentication | SharePoint | Critical 9.1 | 70% |
| Aug 11, 2026 | Windows Ancillary Function Driver for WinSock Use-After-Free | Windows Ancillary Function Driver for WinSock | High 7.0 | 0.3% |
Sources: Known Exploited Vulnerabilities (CISA, public domain), CVE records (cve.org) and EPSS (FIRST). The chance of attacks is the EPSS estimate that someone will try to exploit the flaw in the next 30 days.