CVE-2026-115892Medium· 5.7▾ SunlitWasmtime 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 return…
▾ Sunlit zone — Low / medium · no exploitation signal
impact 31.4 · likelihood 0.1 · exploitation 0
Need a working PoC? Pro members can cast a request and our team develops one — it lands right here.
Stakeholder-Specific Vulnerability Categorization from CISA's ADP record at CVE.org: whether exploitation is observed, whether an attack can be automated, and how much of the system is at stake. The CVSS score shown above comes from the assigning CNA record, not NVD.
Exploit-prediction probability, daily snapshots since Oct 25.
Disclosure to exploitation, from the record and what we observed since indexing it.
Disclosed via CVEORG
0.6%
Last analysed / modified upstream
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.
wasmtime >= 46.0.0, < 48.0.7wasmtime >= 49.0.0, < 49.0.4Refer to the linked advisories for vendor-supplied fixes and affected version ranges.
Affected packages:
wasmtime >= 49.0.0, < 49.0.4Patched in:
wasmtime 49.0.4Connected by shared product, vendor, weakness, or advisory.
CVE-2026-115889Critical· 9.9Wasmtime: Bit-packing in Cranelift compiler causes silent overflow and miscompilation
CVE-2026-115893Critical· 9.9Wasmtime: Cranelift backend on aarch64 can jump to incorrect target on large Wasm `br_table` instruction
RUSTSEC-2026-0378NonePanic lowering a host-created component model stream into a guest that expects a different payload type
CVE-2026-104855Low· 2.0Wasmtime is a runtime for WebAssembly
CVE-2023-41880Low· 2.2Miscompilation of wasm `i64x2.shr_s` instruction with constant input on x86\_64
CVE-2021-39216Medium· 6.3Out-of-bounds read/write and invalid free with `externref`s and GC safepoints in Wasmtime