Wasmtime is a runtime for WebAssembly. In versions from 38.0.0 to before 38.0.3, the implementation of component-model related host-to-wasm trampolines in Wasmtime contained a bug where it's possible to carefully craft a component, which when called in a specific way, would crash the host with a segfault or assert failure. Wasmtime 38.0.3 has been released and is patched to fix this issue. There are no workarounds.
https://github.com/bytecodealliance/wasmtime/security/advisories/GHSA-4h67-722j-5pmc
https://github.com/bytecodealliance/wasmtime/pull/11592
https://github.com/bytecodealliance/wasmtime/commit/192f2fcdadfec9d0cf6b58548a85a7307450cbf5
Published: 2025-10-24
Updated: 2025-10-24
Base Score: 5
Vector: CVSS2#AV:N/AC:L/Au:N/C:N/I:N/A:P
Severity: Medium
Base Score: 7.5
Vector: CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Severity: High
Base Score: 2.1
Vector: CVSS:4.0/AV:N/AC:H/AT:P/PR:L/UI:P/VC:N/VI:N/VA:L/SC:N/SI:N/SA:L
Severity: Low
EPSS: 0.0004