Wasmtime is a runtime for WebAssembly. From 46.0.0 until 48.0.7 and 49.0.4, lowering a host-created component-model stream or future into a guest can omit a required payload-type check after the value passes through guest code and returns through StreamAny, FutureAny, Val::Stream, Val::Future, or an equivalent typed reader. A malicious guest that controls exported function types or returned values can cause the host to pass the type-erased value to a guest expecting a different payload type, which panics the Wasmtime host. This issue is fixed in versions 48.0.7 and 49.0.4.
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Affected Vendors & Products
References
History
Sat, 24 Oct 2026 00:30:00 +0000
| Type | Values Removed | Values Added |
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Bytecodealliance
Bytecodealliance wasmtime |
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| Vendors & Products |
Bytecodealliance
Bytecodealliance wasmtime |
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threat_severity
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cvssV3_1
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Fri, 23 Oct 2026 21:45:00 +0000
| Type | Values Removed | Values Added |
|---|---|---|
| Description | Wasmtime is a runtime for WebAssembly. From 46.0.0 until 48.0.7 and 49.0.4, lowering a host-created component-model stream or future into a guest can omit a required payload-type check after the value passes through guest code and returns through StreamAny, FutureAny, Val::Stream, Val::Future, or an equivalent typed reader. A malicious guest that controls exported function types or returned values can cause the host to pass the type-erased value to a guest expecting a different payload type, which panics the Wasmtime host. This issue is fixed in versions 48.0.7 and 49.0.4. | |
| Title | Wasmtime: Panic lowering a host-created component model stream into a guest that expects a different payload type | |
| Weaknesses | CWE-248 CWE-843 |
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cvssV4_0
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Status: PUBLISHED
Assigner: GitHub_M
Published: 2026-10-23T21:26:54.528Z
Updated: 2026-10-23T21:26:54.528Z
Reserved: 2026-10-23T19:37:27.176Z
Link: CVE-2026-115892
No data.
Status : Deferred
Published: 2026-10-23T22:16:58.633
Modified: 2026-10-23T22:16:58.777
Link: CVE-2026-115892