CVE-2026-119135

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 v3 4.8 MEDIUM

4.8^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 1.2 / Impact : 3.6

Attack Vector NETWORK

Attack Complexity HIGH

Privileges Required LOW

User Interaction REQUIRED

Confidentiality Impact NONE

Integrity Impact NONE

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
https://github.com/bytecodealliance/wasmtime/security/advisories/GHSA-63h4-6cx9-pjfj
https://www.vulncheck.com/advisories/wasmtime-46.0.0-before-48.0.6-and-49.0.0-before-49.0.3-panic-via-streamreader-type-mismatch

Configurations

No configuration.

History

29 Oct 2026, 16:18

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-10-29 16:18

Updated : 2026-10-29 16:18

NVD link : CVE-2026-119135

Mitre link : CVE-2026-119135

CVE.ORG link : CVE-2026-119135

JSON object : View

Products Affected

No product.

CWE

CWE-617

Reachable Assertion

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