CVE-2026-34983 Wasmtime has a use-after-free bug after cloning `wasmtime::Linker`

Wasmtime is a runtime for WebAssembly. In 43.0.0, cloning a wasmtime::Linker is unsound and can result in use-after-free bugs. This bug is not controllable by guest Wasm programs. It can only be triggered by a specific sequence of embedder API calls made by the host. Specifically, the following...

CVE-2026-34983 Wasmtime has a use-after-free bug after cloning `wasmtime::Linker`

Wasmtime is a runtime for WebAssembly. In 43.0.0, cloning a wasmtime::Linker is unsound and can result in use-after-free bugs. This bug is not controllable by guest Wasm programs. It can only be triggered by a specific sequence of embedder API calls made by the host. Specifically, the following...

CVE-2026-34983

Wasmtime 43.0.0 contains a use-after-free bug when cloning wasmtime::Linker, triggered by a specific host embedder API sequence (clone, drop original, use cloned linker). The issue is not controllable by guest Wasm programs and can manifest as a segfault; it does not enable heap corruption or dat...