Cambodia's volcanic hazard is very low, this means no eruption has ever been reported in the countries area.
Cambodia does have a 4,000 year old volcanic crater that is now occupied by a lake named Yeak Laom.

Yeak Laom is a popular tourist destination located in the Ratanakiri province of north-eastern Cambodia. Three miles away from the provincial capital, Banlung. Locals believe the lake is sacred and is used in many ways. People come to Yeak Laom for the clear water and the life that surrounds it.
NEAR BY VOlCANOES
Mount Sinabung the closest active volcano to Cambodia is located in the North Sumatra province, Indonesia. The last time the volcano erupted was in February of 2018. The violent eruption of 2018 sent ash about 20,000 feet into the air and forced about 30,000 people to evacuate the surrounding areas.

VOLCANO ERUPTION SAFETY TIPS
- Make a plan
- Have emergency supplies
- Keep updated on current weather conditions
- Wear personal protective equipment
- evacuate
REFRENCES
- http://thinkhazard.org/en/report/44-cambodia/VA
- https://www.tourismcambodia.com/travelguides/provinces/rattanakiri/what-to-see/216_beung-yeak-loam.htm
- https://www.news.com.au/travel/travel-updates/incidents/mount-sinabung-erupts-sending-pyroclastic-flows-and-searing-gases-down-its-slopes/news-story/8f634b818d9b9b398621deace48112cd