VMware Carbon Black TAU traces DHS-reported HotCroissant, attributed by DHS to North Korea's Hidden Cobra/Lazarus Group, and compares it with the earlier Rifdoor RAT used in attacks dating back to 2015. HotCroissant decodes its C2 address at startup, sends host information, and accepts a broader command set, while newer samples add UPX packing, RC4-and-base64 string protection, dynamic API lookup, and persistence through a scheduled task named "Java Maintenance64". The analysis highlights shared code and protocol traits between HotCroissant and Rifdoor, including one-byte XOR string decoding, similar host-information collection, socket keepalive settings, stream-cipher-style network encryption, opcode-based commands, and transaction IDs. The findings show an evolution from a simpler Rifdoor backdoor toward a more obfuscated Lazarus RAT with expanded remote-control capabilities, including screen viewing and custom encrypted C2 communications.