Wasmtime: Panic lowering a host-created component model stream into a guest that expects a different payload type (bytecodealliance wasmtime)

CVE-2026-115892
MEDIUM 5.7

At a glance

Source
NVD
EPSS
EPSS 0.43 % · percentile 38 ()
State
PUBLISHED
Published
Updated
Assigner
GitHub_M
NVD status
Deferred

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.

Weaknesses (CWE)

  • CWE-843 — Access of Resource Using Incompatible Type
  • CWE-248 — Uncaught Exception

References

Scores

VersionScoreVectorScored by
CVSS 4.0MEDIUM 5.7CVSS:4.0/AV:N/AC:H/AT:P/PR:H/UI:P/VC:N/VI:N/VA:H/SC:N/SI:N/SA:NGitHub_M
CVSS 4.0MEDIUM 5.7CVSS:4.0/AV:N/AC:H/AT:P/PR:H/UI:P/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:XNVD · security-advisories@github.com (Secondary)

European references

Affected products

ProductVersions
bytecodealliance · wasmtimeaffected >= 46.0.0, < 48.0.7 ; affected >= 49.0.0, < 49.0.4

Sources

SourceLicence
CVE List (CVEProject cvelistV5)CVE Program Terms of Use
EPSS (FIRST.org)FIRST — attribution requested
ENISA EUVDENISA — reproduction authorised, source acknowledged
NVD (NIST) via fkie-cad/nvd-json-data-feedsPublic domain — this product uses data from the NVD API but is not endorsed or certified by the NVD