CVE-2022-39394

Wasmtime is a standalone runtime for WebAssembly. Prior to version 2.0.2, there is a bug in Wasmtime’s C API implementation where the definition of the wasmtime_trap_code does not match its declared signature in the wasmtime/trap.h header file. This discrepancy causes the function implementation to perform a 4-byte write into a 1-byte buffer provided by the caller. This can lead to three zero bytes being written beyond the 1-byte location provided by the caller. This bug has been patched and users should upgrade to Wasmtime 2.0.2. This bug can be worked around by providing a 4-byte buffer casted to a 1-byte buffer when calling wasmtime_trap_code. Users of the wasmtime crate are not affected by this issue, only users of the C API function wasmtime_trap_code are affected.