The International Space Station (ISS) has been experiencing a leak since 2019, which has raised concerns for astronaut safety. NASA and Russia have identified 50 "areas of concern" and four cracks in the ISS's Russian segment. While repairs are ongoing, the leak remains a top risk assessment at a level 5 out of 5. To mitigate the issue, Roscosmos has sealed three of the cracks, and NASA astronauts remain on the US side of the station to ensure emergency evacuation is possible.

Source: https://www.livescience.com/space/space-exploration/iss-leaks-among-50-areas-of-concern-for-astronaut-safety-report