Wasmtime: Panic lowering a host-created component model stream into a guest that expects a different payload type
Summary
| CVE | CVE-2026-115892 |
|---|---|
| State | PUBLISHED |
| Assigner | GitHub_M |
| Source Priority | CVE Program / NVD first with legacy fallback |
| Published | 2026-10-23 22:16:58 UTC |
| Updated | 2026-10-23 22:16:58 UTC |
| 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. |
Risk And Classification
Primary CVSS: v4.0 5.7 MEDIUM from [email protected]
CVSS: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:X
Problem Types: CWE-248 | CWE-843 | CWE-843 CWE-843: Access of Resource Using Incompatible Type ('Type Confusion') | CWE-248 CWE-248: Uncaught Exception
| Version | Source | Type | Score | Severity | Vector |
|---|---|---|---|---|---|
| 4.0 | [email protected] | Secondary | 5.7 | MEDIUM | CVSS: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/C... |
| 4.0 | CNA | DECLARED | 5.7 | MEDIUM | CVSS:4.0/AV:N/AC:H/AT:P/PR:H/UI:P/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N |
CVSS v4.0 Breakdown
Attack Vector
NetworkAttack Complexity
HighAttack Requirements
PresentPrivileges Required
HighUser Interaction
PassiveConfidentiality
NoneIntegrity
NoneAvailability
HighSub Conf.
NoneSub Integrity
NoneSub Availability
NoneCVSS: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:X
Vendor Declared Affected Products
| Source | Vendor | Product | Version | Platforms |
|---|---|---|---|---|
| CNA | Bytecodealliance | Wasmtime | affected >= 46.0.0, < 48.0.7 | Not specified |
| CNA | Bytecodealliance | Wasmtime | affected >= 49.0.0, < 49.0.4 | Not specified |
References
| Reference | Source | Link | Tags |
|---|---|---|---|
| github.com/bytecodealliance/wasmtime/commit/48dacc76241f06088e79f3ce1b17... | [email protected] | github.com | |
| github.com/bytecodealliance/wasmtime/pull/14827 | [email protected] | github.com | |
| github.com/bytecodealliance/wasmtime/releases/tag/v49.0.4 | [email protected] | github.com | |
| github.com/bytecodealliance/wasmtime/commit/994549891c8a706cb4f2809f9d17... | [email protected] | github.com | |
| github.com/bytecodealliance/wasmtime/commit/222ff3a65dab9aa7011f8c246937... | [email protected] | github.com | |
| github.com/bytecodealliance/wasmtime/pull/14820 | [email protected] | github.com | |
| github.com/bytecodealliance/wasmtime/security/advisories/GHSA-9pvw-hwfg-... | [email protected] | github.com | |
| github.com/bytecodealliance/wasmtime/releases/tag/v48.0.7 | [email protected] | github.com | |
| github.com/bytecodealliance/wasmtime/pull/14819 | [email protected] | github.com | |
| CVE Program record | CVE.ORG | www.cve.org | canonical |
| NVD vulnerability detail | NVD | nvd.nist.gov | canonical, analysis |
No vendor comments have been submitted for this CVE.
There are currently no legacy QID mappings associated with this CVE.