CVE-2026-27572 Wasmtime can panic when adding excessive fields to a `wasi:http/types.fields` instance

Wasmtime is a runtime for WebAssembly. Prior to versions 24.0.6, 36.0.6, 4.0.04, 41.0.4, and 42.0.0, Wasmtime's implementation of the wasi:http/types.fields resource is susceptible to panics when too many fields are added to the set of headers. Wasmtime's implementation in the wasmtime-wasi-http...

CVE-2026-27572

Wasmtime is a runtime for WebAssembly. Prior to versions 24.0.6, 36.0.6, 4.0.04, 41.0.4, and 42.0.0, Wasmtime's implementation of the wasi:http/types.fields resource is susceptible to panics when too many fields are added to the set of headers. Wasmtime's implementation in the wasmtime-wasi-http...

CVE-2026-27572

Wasmtime (WebAssembly runtime) is affected by CVE-2026-27572 in the wasi:http/types.fields implementation. Prior to patched releases (Wasmtime 24.0.6, 36.0.6, 40.0.4, 41.0.4, and 42.0.0), the wasmtime-wasi-http crate uses a data structure that panics when the headers field set becomes excessively...

CVE-2026-27204

Wasmtime is a runtime for WebAssembly. Prior to versions 24.0.6, 36.0.6, 4.0.04, 41.0.4, and 42.0.0, Wasmtime's implementation of WASI host interfaces are susceptible to guest-controlled resource exhaustion on the host. Wasmtime did not appropriately place limits on resource allocations requested...

CVE-2026-27204 Wasmtime WASI implementations are vulnerable to guest-controlled resource exhaustion

Wasmtime is a runtime for WebAssembly. Prior to versions 24.0.6, 36.0.6, 4.0.04, 41.0.4, and 42.0.0, Wasmtime's implementation of WASI host interfaces are susceptible to guest-controlled resource exhaustion on the host. Wasmtime did not appropriately place limits on resource allocations requested...

CVE-2026-27204

CVE-2026-27204 involves Wasmtime’s WASI host interfaces, where guest code could exhaust host resources due to insufficient limits on resource allocations. Affected versions prior to fixes include 24.0.6, 36.0.6, 40.0.4, 41.0.4, and 42.0.0. The fixes are released in Wasmtime 24.0.6, 36.0.6, 40.0.4...

CVE-2026-27204

Wasmtime is a runtime for WebAssembly. Prior to versions 24.0.6, 36.0.6, 4.0.04, 41.0.4, and 42.0.0, Wasmtime's implementation of WASI host interfaces are susceptible to guest-controlled resource exhaustion on the host. Wasmtime did not appropriately place limits on resource allocations requested...

CVE-2026-27204 Wasmtime WASI implementations are vulnerable to guest-controlled resource exhaustion

Wasmtime is a runtime for WebAssembly. Prior to versions 24.0.6, 36.0.6, 4.0.04, 41.0.4, and 42.0.0, Wasmtime's implementation of WASI host interfaces are susceptible to guest-controlled resource exhaustion on the host. Wasmtime did not appropriately place limits on resource allocations requested...

CVE-2026-27204 Wasmtime WASI implementations are vulnerable to guest-controlled resource exhaustion

Wasmtime is a runtime for WebAssembly. Prior to versions 24.0.6, 36.0.6, 4.0.04, 41.0.4, and 42.0.0, Wasmtime's implementation of WASI host interfaces are susceptible to guest-controlled resource exhaustion on the host. Wasmtime did not appropriately place limits on resource allocations requested...

CVE-2026-27195 Wasmtime is vulnerable to panic when dropping a `[Typed]Func::call_async` future

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 TypedFunc::callasync which made it capable of calling async-typed guest export functions. However, that implementation had a bu...

CVE-2026-27195

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 TypedFunc::callasync which made it capable of calling async-typed guest export functions. However, that implementation had a bu...

CVE-2026-27195 Wasmtime is vulnerable to panic when dropping a `[Typed]Func::call_async` future

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 TypedFunc::callasync which made it capable of calling async-typed guest export functions. However, that implementation had a bu...

CVE-2026-27195 Wasmtime is vulnerable to panic when dropping a `[Typed]Func::call_async` future

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 TypedFunc::callasync which made it capable of calling async-typed guest export functions. However, that implementation had a bu...

CVE-2026-27195

CVE-2026-27195 affects Wasmtime in versions where component-model-async is default (from 39.0.0). The bug causes a panic when a host embeds calls to wasmtime::component::[Typed]Func::call_async, drops the returned Future after polling, and then reuses the same component instance before the first ...

CVE-2026-27195

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 TypedFunc::callasync which made it capable of calling async-typed guest export functions. However, that implementation had a bu...

GHSA-243V-98VX-264H Wasmtime can panic when adding excessive fields to a `wasi:http/types.fields` instance

Impact Wasmtime's implementation of the wasi:http/types.fields resource is susceptible to panics when too many fields are added to the set of headers. Wasmtime's implementation in the wasmtime-wasi-http crate is backed by a data structure which panics when it reaches excessive capacity and this...

Wasmtime can panic when adding excessive fields to a `wasi:http/types.fields` instance

Impact Wasmtime's implementation of the wasi:http/types.fields resource is susceptible to panics when too many fields are added to the set of headers. Wasmtime's implementation in the wasmtime-wasi-http crate is backed by a data structure which panics when it reaches excessive capacity and this...

Wasmtime WASI implementations are vulnerable to guest-controlled resource exhaustion

Impact Wasmtime's implementation of WASI host interfaces are susceptible to guest-controlled resource exhaustion on the host. Wasmtime did not appropriately place limits on resource allocations requested by the guests. This serves as a Denial of Service vector where a guest can induce a range of...

GHSA-852M-CVVP-9P4W Wasmtime WASI implementations are vulnerable to guest-controlled resource exhaustion

Impact Wasmtime's implementation of WASI host interfaces are susceptible to guest-controlled resource exhaustion on the host. Wasmtime did not appropriately place limits on resource allocations requested by the guests. This serves as a Denial of Service vector where a guest can induce a range of...

Wasmtime is vulnerable to panic when dropping a `[Typed]Func::call_async` future

The affected versions of Wasmtime can panic if the host embedder drops the future returned by wasmtime::component::TypedFunc::callasync before it resolves. Details Starting with Wasmtime 39.0.0, the component-model-async feature became the default, which brought with it a new implementation of...