FamousSparrow, a new cyberespionage group, has been targeting several entities across the globe including the hotel industry and high-end entities including engineering companies, law firms, governments, and international organizations. These threat-actors have targeted individuals from France, UK, Israel, Saudi Arabia, Brazil, Canada, Taiwan, Burkina Faso and more since 2019 purely for espionage purposes. FamousSparrow utilizes several attack vectors in internet-facing web applications to breach their targets, including the widely known ProxyLogon Exchange security flaws. The threat group has a custom crafted backdoor, properly dubbed SparrowDoor, as well as two variants of Mimikatz. While FamousSparrow is believed to operate independent of other threat groups, based on some tactics, techniques, and procedures of the espionage group, researchers do see some connections to other advanced persistent threat (APT) groups including DRBControl and SparklingGoblin. The CTAPT will continue to monitor the movements of this new threat group and will provide updates as needed.