Cybercriminals use OpenDocument Text (ODT) files to distribute malware that is typically blocked by antivirus engines. ODT files are archives that can hold text, images, and objects, such as XML-based files that can be opened by Microsoft Office and similar, open-source software (LibreOffice, OpenOffice) The campaigns target English and Arabic-speaking users. Researchers say the use of less popular file formats such as ODT may increase the potential of specifically targeted attacks.
Source: https://www.bleepingcomputer.com/news/security/under-detected-odt-files-deliver-common-remote-access-trojans/