TStark is a threat actor identified by X-Ops, associated with a cluster of devices that executed the bookmark buffer overflow exploit targeting CVE-2020-15069 (T1203). The actor exhibited odd telemetry behavior indicative of intermittent VPN usage, switching between IP addresses geolocated to Hong Kong and Chengdu. Analysis revealed malware samples for Mac OS X and iOS, as well as IFRAME injection code exploiting a WebAssembly vulnerability (T1189). Additionally, TStark was linked to the development of libsophos.so and the deployment of malicious payloads across their devices.