#VU125759 Type Confusion in Wasmtime - CVE-2026-35186
Published: April 10, 2026
Vulnerability identifier: #VU125759
Vulnerability risk: Low
CVSSv4.0: CVSS:4.0/AV:N/AC:L/AT:P/PR:L/UI:N/VC:L/VI:L/VA:H/SC:N/SI:N/SA:N/E:U/U:Clear
CVE-ID: CVE-2026-35186
CWE-ID: CWE-843
Exploitation vector: Remote access
Exploit availability:
No public exploit available
Vulnerable software:
Wasmtime
Wasmtime
Software vendor:
Bytecode Alliance
Bytecode Alliance
Description
The vulnerability allows a remote user to cause a denial of service and disclose sensitive information.
The vulnerability exists due to improper type handling in the Winch compiler backend when translating the table.grow operator. A remote user can cause a WebAssembly module to use the result of table.grow in memory operations to cause a denial of service and disclose sensitive information.
By default, the issue results in a process abort because the affected access reaches unmapped memory before linear memory. Information disclosure of up to 16 bytes is possible only when guard pages before linear memory are disabled.
Remediation
Install security update from vendor's website.