# Security
> TBS
## Mapping of Instructions
### Type Conversions
WASM have `i32`, `i64`, `f32`, `f64` as number types while EVM bytecode
only supports arithmetic operations for 256-bits integers.
> TODO: Add more risk conditions.
### Stack Operations
> TBA
### Memory Operations
The memory related operations in WASM are dangerous for Zink's implementation.
WASM is using 32-bits offsets from the MVP spec while EVM is using 256-bits offsets,
so it may cause memory overwrite problems.
The instructions need to be checked:
- `i32.store`
- `i64.store`
- `f32.store`
- `f64.store`
- `i32.store8`
- `i64.store8`
- `i32.store16`
- `i64.store16`
- `memory.size`
- `memory.grow`
TODO: check if it is possible to manage this issue with handling `memory.size` and `memory.grow`
in a proper way.