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README.md

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-> 🚨**ATTENTION**🚨 The NIST 800-53 mappings have migrated to CTID’s new [Mappings Explorer](https://center-for-threat-informed-defense.github.io/mappings-explorer/) project. You can find the latest mappings on the Mappings Explorer website. This website presents threat and mitigation data in easily accessible and customizable ways, enabling cyber defenders to understand how security controls and capabilities map onto adversary behaviors catalogued in the [MITRE ATT&CK®](https://attack.mitre.org/) knowledge base. The source code and raw data for the Mappings Explorer project can be found in the [mappings-explorer repository](https://github.com/center-for-threat-informed-defense/mappings-explorer/).
+> 🚨**ATTENTION**🚨 The NIST 800-53 mappings have migrated to CTID’s new [Mappings Explorer](https://center-for-threat-informed-defense.github.io/mappings-explorer/external/nist/) project. You can find the latest mappings on the Mappings Explorer website. This website presents threat and mitigation data in easily accessible and customizable ways, enabling cyber defenders to understand how security controls and capabilities map onto adversary behaviors catalogued in the [MITRE ATT&CK®](https://attack.mitre.org/) knowledge base. The source code and raw data for the Mappings Explorer project can be found in the [mappings-explorer repository](https://github.com/center-for-threat-informed-defense/mappings-explorer/).
 
 # Security Control Framework Mappings to ATT&CK
 This repository contains security control framework mappings to MITRE ATT&CK® with supporting documentation and resources. These mappings provide a critically important resource for organizations to assess their security control coverage against real-world threats as described in the ATT&CK knowledge base and provide a foundation for integrating ATT&CK-based threat information into the risk management process. This work was developed by the [Center for Threat-Informed Defense](https://ctid.mitre-engenuity.org/) in collaboration with our participants.