Incorrect calculation in Wasmtime - CVE-2026-34946
Published: April 10, 2026
Vulnerability identifier: #VU125757
CSH Severity: Low
CVSS v4: 6.8 [CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:A/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N]
CVE-ID: CVE-2026-34946
CWE-ID: CWE-682
Exploitation vector: Remote access
Exploit availability:
No public exploit available
Vulnerability details
The vulnerability allows a remote user to cause a denial of service.
The vulnerability exists due to incorrect table indexing in the Winch compiler when compiling the table.fill instruction. A remote user can compile a valid guest that uses table.fill to cause a denial of service.
User interaction is required to process the crafted guest.
Affected software
Wasmtime
How to mitigate CVE-2026-34946
Install security update from vendor's website.
Wasmtime - addressed in versions 36.0.7, 42.0.2, 43.0.1