CVE-2026-34944 (GCVE-0-2026-34944)
Vulnerability from cvelistv5
Published
2026-04-09 18:38
Modified
2026-04-13 15:38
CWE
Summary
Wasmtime is a runtime for WebAssembly. Prior to 24.0.7, 36.0.7, 42.0.2, and 43.0.1, On x86-64 platforms with SSE3 disabled Wasmtime's compilation of the f64x2.splat WebAssembly instruction with Cranelift may load 8 more bytes than is necessary. When signals-based-traps are disabled this can result in a uncaught segfault due to loading from unmapped guard pages. With guard pages disabled it's possible for out-of-sandbox data to be loaded, but this data is not visible to WebAssembly guests. This vulnerability is fixed in 24.0.7, 36.0.7, 42.0.2, and 43.0.1.
Impacted products
Vendor Product Version
bytecodealliance wasmtime Version: < 24.0.7
Version: >= 25.0.0, < 36.0.7
Version: >= 37.0.0, < 42.0.2
Version: >= 43.0.0, < 44.0.1
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Show details on NVD website


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  • Seen: The vulnerability was mentioned, discussed, or seen somewhere by the user.
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