Prevents the establishment of cellular antiviral state by blocking the interferon-alpha/beta (IFN-alpha/beta) and IFN-gamma signaling pathways. Blocks the IFN-induced nuclear accumulation of host phosphorylated STAT1 by interacting with the STAT1-binding region of host importins. Alternatively interacts also directly with host STAT1 and may additionally inhibit its non-phosphorylated form. Plays a role in assembly of viral nucleocapsid and virion budding. May act as a minor matrix protein that plays a role in assembly of viral nucleocapsid and virion budding. Interacts with host importins KPNA1, KPNA5 and KPNA6. Interacts with host STAT1. Interacts with host KEAP1; this interaction activates host transcription factor NRF2 by blocking its interaction with KEAP1. In virion, localizes on the intravirional side of the membrane. In the host cell, it is found associated with virus-induced membrane proliferation foci and to the plasma membrane where budding takes place (By similarity). Belongs to the filoviridae membrane-associated protein VP24 family.