{"schemaVersion":3,"id":"CVE-2026-34983","aliases":["PYSEC-2026-151","GHSA-hfr4-7c6c-48w2","RUSTSEC-2026-0090","UBUNTU-CVE-2026-34983","DEBIAN-CVE-2026-34983","CGA-cmr6-q452-x89g","CGA-rhjc-fhw2-64v4"],"status":"published","duplicateOf":null,"title":null,"description":"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 steps must occur to trigger the bug clone a wasmtime::Linker, drop the original linker instance, use the new, cloned linker instance, resulting in a use-after-free. 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