Read the original article: MosaicRegressor: Lurking in the Shadows of UEFI
We found a compromised UEFI firmware image that contained a malicious implant. To the best of our knowledge, this is the second known public case where malicious UEFI firmware in use by a threat actor was found in the wild.
Read the original article: MosaicRegressor: Lurking in the Shadows of UEFI