The cargo tanks would normally have a vapour space made of exhaust gas (inert gas) from the boiler which is less than 5% oxygen. However, this ship's inert gas

The cargo tanks would normally have a vapour space made of exhaust gas (inert gas) from the boiler which is less than 5% oxygen. However, this ship's inert gas system broke down years ago so it probably has a flammable atmosphere in its cargo tanks. Potentially the crude has weathered off so much over the years that it's no longer degassing, and less scientifically I think if the tank vapours haven't found an ignition source yet, they probably won't. However corrosion never sleeps. The cargo tanks don't leak straight into the sea; you have ballast tanks too. If I had to guess, the next threat might be a leak into the pump room resulting in fire. But ships have a periodic inspection regime under that they call "class rules" - this ship hasn't been in class for 5 years. That is an insane period of time to be carrying hydrocarbon while being out of class. There are hundreds of threats to this tanker and it is difficult to predict how it could fail, including complete loss of the vessel.