CVE-2026-44216
Panic when allocating a table exceeding the size of the host's address space
Description
Wasmtime is a runtime for WebAssembly. From 30.0.0 to 36.0.8, 43.0.2, and 44.0.1, Wasmtime's allocation logic for a WebAssembly table contained checked arithmetic which panicked on overflow. This overflow is possible to trigger, and thus panic, when a table with an extremely large size is allocated. This is possible with the WebAssembly memory64 proposal where tables can have sizes in the 64-bit range as opposed to the previous 32-bit range which would not overflow. The panic happens when attempting to create a very large table, such as when instantiating a WebAssembly module or component. This vulnerability is fixed in 36.0.8, 43.0.2, and 44.0.1.
How to fix CVE-2026-44216
To remediate CVE-2026-44216, upgrade the affected package to a fixed version below.
- —upgrade to 36.0.8 or later
- —upgrade to 36.0.8 or later
- —no fix listed
Is CVE-2026-44216 being exploited?
Low — EPSS is 0.0%, meaning exploitation activity has not been observed at scale.
Affected packages (3)
- >= 30.0.0, < 36.0.8
- >= 30.0.0, < 36.0.8, >= 37.0.0, < 43.0.2, >= 44.0.0, < 44.0.1
- from 0
CVSS scores
| Source | Version | Severity | Vector |
|---|---|---|---|
| osv | CVSS 4.0 | — | CVSS:4.0/AV:N/AC:L/AT:P/PR:L/UI:P/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N |
| osv | CVSS 3.1 | HIGH7.5 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H |