Wasmtime 46.0.0 before 48.0.6 and 49.0.0 before 49.0.3 panics when the host reads a component model stream as a different Rust item type than it was created with, because the host-to-host read path asserts matching TypeIds instead of returning an error. Guest code can return a host-created StreamReader<U> that the embedder reads as StreamReader<T>, where both types map to the same component model type, crashing the embedding process.
Metrics
Affected Vendors & Products
Advisories
No advisories yet.
Fixes
Solution
No solution given by the vendor.
Workaround
No workaround given by the vendor.
References
History
Thu, 29 Oct 2026 16:15:00 +0000
| Type | Values Removed | Values Added |
|---|---|---|
| Description | Wasmtime 46.0.0 before 48.0.6 and 49.0.0 before 49.0.3 panics when the host reads a component model stream as a different Rust item type than it was created with, because the host-to-host read path asserts matching TypeIds instead of returning an error. Guest code can return a host-created StreamReader<U> that the embedder reads as StreamReader<T>, where both types map to the same component model type, crashing the embedding process. | |
| Title | Wasmtime 46.0.0 before 48.0.6 and 49.0.0 before 49.0.3 Panic via StreamReader Type Mismatch | |
| First Time appeared |
Bytecodealliance
Bytecodealliance wasmtime |
|
| Weaknesses | CWE-617 | |
| CPEs | cpe:2.3:a:bytecodealliance:wasmtime:*:*:*:*:*:*:*:* | |
| Vendors & Products |
Bytecodealliance
Bytecodealliance wasmtime |
|
| References |
| |
| Metrics |
cvssV3_1
|
Projects
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Status: PUBLISHED
Assigner: VulnCheck
Published:
Updated: 2026-10-29T15:58:15.914Z
Reserved: 2026-10-29T14:26:15.522Z
Link: CVE-2026-119135
No data.
Status : Deferred
Published: 2026-10-29T16:18:06.757
Modified: 2026-10-29T16:18:06.870
Link: CVE-2026-119135
No data.
OpenCVE Enrichment
Updated: 2026-10-29T20:45:14Z
Weaknesses