forked from p15670423/monkey
75 lines
2.9 KiB
Markdown
75 lines
2.9 KiB
Markdown
---
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title: "Zerologon"
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date: 2021-01-31T19:46:12+05:30
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draft: false
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tags: ["exploit", "windows"]
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---
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The Zerologon exploiter exploits [CVE-2020-1472](https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2020-1472).
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### Description
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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).
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To download the relevant security update and read more, click [here](https://msrc.microsoft.com/update-guide/en-US/vulnerability/CVE-2020-1472).
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### A note on safety
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This exploiter is not safe for production or other sensitive environments. It
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is, therefore, **not** enabled by default.
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During successful exploitation, the Zerologon exploiter:
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* will temporarily change the target domain controller's password.
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* may break the target domain controller's communication with other systems in the network, affecting functionality.
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* may change the administrator's password.
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* will *attempt* to revert all changes.
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While the Zerologon exploiter is usually successful in reverting its changes
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and restoring the original passwords, it sometimes fails. Restoring passwords
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manually after the Zerologon exploiter has run is nontrivial. For information
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on restoring the original passwords, see the section on manually restoring your
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passwords.
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To minimize the risk posed by this exploiter, it is recommended that this
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exploiter be run _only_ against VMs with a recent snapshot and _only_ in
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testing or staging environments.
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### Manually restoring your password
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This exploiter attempts to restore the original passwords after exploitation.
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It is usually successful, but it sometimes fails. If this exploiter has changed
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a password but was unable to restore the original, you can try the following
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methods to restore the original password.
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#### Restore the VM from a recent snapshot
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If the affected system is a virtual machine, the simplest way to restore it to
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a working state is to revert to a recent snapshot.
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#### Restore the administrator's password
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If you are unable to log in as the administrator, you can follow the
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instructions
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[here](https://www.top-password.com/knowledge/reset-windows-server-2019-password.html)
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to regain access to the system.
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#### Use Reset-ComputerMachinePassword
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If you are able to login as the administrator, you can use the
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[Reset-ComputerMachinePassword](https://docs.microsoft.com/en-us/powershell/module/microsoft.powershell.management/reset-computermachinepassword?view=powershell-5.1)
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powershell command to restore the domain controller's password.
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#### Try a zerologon password restoration tool
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If all other approaches fail, you can try the tools and steps found
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[here](https://github.com/risksense/zerologon).
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### Notes
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* The Infection Monkey exploiter implementation is based on implementations by [@dirkjanm](https://github.com/dirkjanm/CVE-2020-1472/) and [@risksense](https://github.com/risksense/zerologon).
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