[BOOKWORM](https://attack.mitre.org/software/S1226) is a modular trojan known to be leveraged by [Mustang Panda](https://attack.mitre.org/groups/G0129) and was first observed utilized in 2015. [BOOKWORM](https://attack.mitre.org/software/S1226) was later updated in late 2021 and the fall of 2022 to launch shellcode represented as UUID parameters. (Citation: Broadcom)(Citation: Unit42 Bookworm Nov2015)(Citation: Palo Alto Networks, Unit 42)