Yes. Some models are specifically designed and tested to provide protection against both fire and water. However, a conventional fire-resistant safe or fire-resistant cabinet is generally not waterproof: fire-resistance certification does not guarantee protection against submersion.
This is particularly important for a safe installed in a basement. During a fire, the basement may fill with firefighting water while the safe itself remains relatively cool. Intumescent seals only expand when exposed to sufficient heat and may therefore not yet provide a complete seal. Keyholes and cable openings can also provide possible entry points for water.
Some compact fire-resistant chests have separately tested water protection, with certain models offering protection against submersion for up to 72 hours. An exceptional example was the former KASO DS 4000 data safe: certain models were independently tested by being submerged at a depth of three metres for four hours.
Where there is a risk of flooding, the location of the safe is also important. Installing it in an area that is unlikely to become submerged, or placing it on a sufficiently high plinth, can considerably reduce the risk.