CVE 1.8 LOW

Wasmtime provides unsound API access to a WebAssembly shared linear memory_CVE-2025-64345

1.8 / 10
LOW
CVSS:3.1/AV:L/AC:H/PR:H/UI:R/S:U/C:N/I:L/A:N

Description

Wasmtime is a runtime for WebAssembly. Prior to version 38.0.4, 37.0.3, 36.0.3, and 24.0.5, Wasmtime's Rust embedder API contains an unsound interaction where a WebAssembly shared linear memory could be viewed as a type which provides safe access to the host (Rust) to the contents of the linear memory. This is not sound for shared linear memories, which could be modified in parallel, and this could lead to a data race in the host. Patch releases have been issued for all supported versions of Wasmtime, notably: 24.0.5, 36.0.3, 37.0.3, and 38.0.4. These releases reject creation of shared memories via `Memory::new` and shared memories are now excluded from core dumps. As a workaround, eembeddings affected by this issue should use `SharedMemory::new` instead of `Memory::new` to create shared memories. Affected embeddings should also disable core dumps if they are unable to upgrade. Note that core dumps are disabled by default but the wasm threads proposal (and shared memory) is enabled by default.

Basic Information

ID CVE-2025-64345
Source GitHub_M
Published Nov 12, 2025 at 21:25
Modified Nov 12, 2025 at 21:40

Affected Product

Vendor bytecodealliance
Product wasmtime
Version >= 38.0.1, < 38.0.4
Affected Versions bytecodealliance wasmtime >= 38.0.1, < 38.0.4
bytecodealliance wasmtime >= 37.0.0, < 37.0.3
bytecodealliance wasmtime >= 26.0.0, < 36.0.3
bytecodealliance wasmtime < 24.0.5

CWE Classification

References

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