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.
Project Subscriptions
No data.
Advisories
| Source | ID | Title |
|---|---|---|
Github GHSA |
GHSA-qqfj-4vcm-26hv | Wasmtime segfault or unused out-of-sandbox load with `f64x2.splat` operator on x86-64 |
Fixes
Solution
No solution given by the vendor.
Workaround
No workaround given by the vendor.
References
History
Thu, 09 Apr 2026 19:00:00 +0000
| Type | Values Removed | Values Added |
|---|---|---|
| Description | 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. | |
| Title | Wasmtime segfault or unused out-of-sandbox load with `f64x2.splat` operator on x86-64 | |
| Weaknesses | CWE-248 | |
| References |
| |
| Metrics |
cvssV4_0
|
Projects
Sign in to view the affected projects.
Status: PUBLISHED
Assigner: GitHub_M
Published:
Updated: 2026-04-09T18:38:16.182Z
Reserved: 2026-03-31T17:27:08.660Z
Link: CVE-2026-34944
No data.
Status : Received
Published: 2026-04-09T19:16:24.187
Modified: 2026-04-09T19:16:24.187
Link: CVE-2026-34944
No data.
OpenCVE Enrichment
No data.
Weaknesses
Github GHSA