CVE-2026-119135 (GCVE-0-2026-119135)

Vulnerability from cvelistv5 – Published: 2026-10-29 15:58 – Updated: 2026-10-29 15:58
VLAI
Title
Wasmtime 46.0.0 before 48.0.6 and 49.0.0 before 49.0.3 Panic via StreamReader Type Mismatch
Summary
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.
Severity
5.9 (Medium)
CVSS:4.0/AV:N/AC:H/AT:P/PR:L/UI:P/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N
4.8 (Medium)
CVSS:3.1/AV:N/AC:H/PR:L/UI:R/S:U/C:N/I:N/A:H
CWE
Assigner
VulnCheck CNA under the mitre root
CNA scorecard B 84/100 over 7140 records in the last 180 days details
References
Impacted products
Vendor Product Version CPE status
bytecodealliance wasmtime Affected: 46.0.0 , < 48.0.6 (semver)
Unaffected: 48.0.6 (semver)
Affected: 49.0.0 , < 49.0.3 (semver)
Unaffected: 49.0.3 (semver)
    cpe:2.3:a:bytecodealliance:wasmtime:*:*:*:*:*:*:*:*
    cpe:2.3:a:bytecodealliance:wasmtime:*:*:*:*:*:*:*:*
Create a notification for this product.
Date Public
2026-10-14 00:00
Credits
tschneidereit
Show details on NVD website
To clipboard 

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    "dateReserved": "2026-10-29T14:26:15.522Z",
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}



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