CVE-2026-44216
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.
- CVSS 4.0
- 5.9
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 - CVSS 3.1
- 7.5
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H - EPSS
- 0.3% chance of exploitation in the next 30 days; higher than 24% of CVEs (scores of 2026-10-25)
- CWEs
- CWE-770, CWE-190
- Published
- Modified
- Record from
- the NVD, synced
Affected
- bytecodealliance:wasmtime
Packages (OSV)
| Advisory | Ecosystem | Package | Affected | Fixed in |
|---|---|---|---|---|
| GHSA-p8xm-42r7-89xg | crates.io | wasmtime | >=30.0.0 <36.0.8 | 36.0.8 |
| GHSA-p8xm-42r7-89xg | crates.io | wasmtime | >=37.0.0 <43.0.2 | 43.0.2 |
| RUSTSEC-2026-0114 | crates.io | wasmtime | >=30.0.0 <36.0.8 >=37.0.0 <43.0.2 >=44.0.0 <44.0.1 | 36.0.8, 43.0.2, 44.0.1 |
References
- https://github.com/bytecodealliance/wasmtime/security/advisories/GHSA-p8xm-42r7-89xg
- https://access.redhat.com/errata/RHSA-2026:45341
- https://access.redhat.com/security/cve/CVE-2026-44216
- https://bugzilla.redhat.com/show_bug.cgi?id=2477467
- https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-44216.json