Improper control of a resource through its lifetime in Wasmtime - CVE-2026-27195
Published: April 23, 2026
Vulnerability identifier: #VU127044
CSH Severity: Low
CVSS v4.0: CVSS:4.0/AV:N/AC:L/AT:P/PR:L/UI:A/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:U/U:Clear
CVE-ID: CVE-2026-27195
CWE-ID: CWE-664
Exploitation vector: Remote access
Exploit availability:
No public exploit available
Vendor: Bytecode Alliance
Affected software:
Wasmtime
Wasmtime
Detailed vulnerability description
The vulnerability allows a remote user to cause a denial of service.
The vulnerability exists due to improper state management in wasmtime::component::[Typed]Func::call_async when dropping a returned future before it resolves and then invoking the same component instance again. A remote user can drop a previously polled call_async future and trigger another call on the same component instance to cause a denial of service.
Only instances using the component-model-async feature are affected, and exploitation requires the future to have been polled and yielded before being dropped.
How to mitigate CVE-2026-27195
Install security update from vendor's website.