REF4033 CbsMsgApi Loader Execution

nomit vyas@xoxo

•updated Jun 22, 2026•1•0•7

Detects the execution of CbsMsgApi.exe, which is the initial loader used by the REF4033 group to install the BADIIS IIS module and create a persistence service. The detection is based on the specific filename or the known MD5 hash of the loader.