CVE-2026-119135
Deferred
Deferred - Pending Action
Type Confusion in Wasmtime Component Model Stream Handling
Vulnerability report for CVE-2026-119135, including description, CVSS score, EPSS score, affected products, exploitability, helpful resources, and attack-flow context.
Publication date: 2026-10-29
Last updated on: 2026-10-29
Assigner: VulnCheck
Description
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.
CVSS Scores
EPSS Scores
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| Percentile: |
Meta Information
Affected Vendors & Products
| Vendor | Product | Version / Range |
|---|---|---|
| bytecodealliance | wasmtime | 46.0.0 |
| bytecodealliance | wasmtime | 49.0.0 |
Helpful Resources
Exploitability
CWE
KEV
| CWE ID | Description |
|---|---|
| CWE-617 | The product contains an assert() or similar statement that can be triggered by an attacker, which leads to an application exit or other behavior that is more severe than necessary. |
