JLSEC-2026-1360 Wasmtime: Miscompiled guest heap access enables sandbox escape on aarch64 Cranelift

Impact Wasmtime's Cranelift compilation backend contains a bug on aarch64 when performing a certain shape of heap accesses which means that the wrong address is accessed. When combined with explicit bounds checks a guest WebAssembly module this can create a situation where there are two diverging...

Wasmtime with Winch compiler backend on aarch64 may allow a sandbox-escaping memory access

Impact Wasmtime with its Winch baseline non-default compiler backend may allow properly constructed guest Wasm to access host memory outside of its linear-memory sandbox. This vulnerability requires use of the Winch compiler -Ccompiler=winch. By default, Wasmtime uses its Cranelift backend, not...

PYSEC-2021-87

Cranelift is an open-source code generator maintained by Bytecode Alliance. It translates a target-independent intermediate representation into executable machine code. There is a bug in 0.73 of the Cranelift x64 backend that can create a scenario that could result in a potential sandbox escape i...