Off-by-one in Wasmtime - CVE-2023-41880
Published: September 14, 2023 / Updated: April 23, 2026
Wasmtime
Bytecode Alliance
Description
The vulnerability allows a remote user to cause incorrect computation results.
The vulnerability exists due to an off-by-one error in the Cranelift code generator for the WebAssembly i64x2.shr_s instruction when compiling WebAssembly on x86_64 with a constant shift amount larger than 32. A remote privileged user can execute a specially crafted WebAssembly program to cause incorrect computation results.
This issue is not an escape from the WebAssembly sandbox and affects only x86_64 hosts.