“contains CSAM” is likely an unarguable fact.

“unsafe” is a term that is both broader and more vague, so I would consider it opinion unless backed up by appropriate facts (like “contains CSAM”, “contains malware”, and so forth).

> “contains CSAM” is likely an unarguable fact.

Except when it isn't. CSAM may be easier to define and identify than pornography, but there still exists material that treads a moral grey area.