CVE-2026-27195Improper Handling of Exceptional Conditions in Wasmtime

Severity
6.9MEDIUMNVD
EPSS
0.1%
top 78.66%
CISA KEV
Not in KEV
Exploit
No known exploits
Timeline
PublishedFeb 24

Description

Wasmtime is a runtime for WebAssembly. Starting with Wasmtime 39.0.0, the `component-model-async` feature became the default, which brought with it a new implementation of `[Typed]Func::call_async` which made it capable of calling async-typed guest export functions. However, that implementation had a bug leading to a panic under certain circumstances: First, the host embedding calls `[Typed]Func::call_async` on a function exported by a component, polling the returned `Future` once. Second, the c

CVSS vector

CVSS:4.0/AV:N/AC:H/AT:P/PR:L/UI:P/VC:N/VI:N/VA:H/SC:N/SI:N/SA:H

Affected Packages4 packages

NVDbytecodealliance/wasmtime39.0.040.0.4+1
crates.iobytecodealliance/wasmtime39.0.040.0.4+1
CVEListV5bytecodealliance/wasmtime>= 39.0.0, < 40.0.4, >= 41.0.0, < 41.0.4+1

Patches

🔴Vulnerability Details

3
OSV
Wasmtime is vulnerable to panic when dropping a `[Typed]Func::call_async` future2026-02-24
GHSA
Wasmtime is vulnerable to panic when dropping a `[Typed]Func::call_async` future2026-02-24
OSV
Panic when dropping a `[Typed]Func::call_async` future2026-02-24

📋Vendor Advisories

2
Red Hat
wasmtime: Wasmtime: Denial of Service via repeated async function calls2026-02-24
Debian
CVE-2026-27195: rust-wasmtime - Wasmtime is a runtime for WebAssembly. Starting with Wasmtime 39.0.0, the `compo...2026

🕵️Threat Intelligence

1
Wiz
CVE-2026-27195 Impact, Exploitability, and Mitigation Steps | Wiz