Description
Wasmtime 42.0.0 before 48.0.6 and 49.0.0 before 49.0.3 contains insufficient checks in Store when mixing async-style and sync-style WebAssembly calls. Embedders re-entering WebAssembly via sync APIs from host functions called asynchronously can trigger runtime panics or unsound cross-thread movement of !Send host variables.
References2
Metrics
- CVSS 3.1
-
4.8
MEDIUM
Score source: NVD
CVSS:3.1/AV:N/AC:H/PR:L/UI:R/S:U/C:N/I:N/A:H - CVSS 4.0
-
5.9
MEDIUM
Score source: CNA
CVSS:4.0/AV:N/AC:H/AT:P/PR:L/UI:P/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X - EPSS — exploit probability
- 0% percentile: 11 · as of 2 November 2026
- CWE
- CWE-1265
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