CVE-2022-39393 HIGH

CVE-2022-39393: Wasmtime vulnerable to data leakage between instances in the pooling allocator

Vendor Bytecodealliance
Product wasmtime
Weakness CWE-226
Published November 10, 2022
Last update May 2, 2025

CVSS base score

8.6/10
Attack vector Network
Attack complexity Low
Privileges required None
User interaction None
Confidentiality High
Integrity None

CVSS vector

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:N/A:N

What the vulnerability does

01Description

Wasmtime is a standalone runtime for WebAssembly. Prior to versions 2.0.2 and 1.0.2, there is a bug in Wasmtime's implementation of its pooling instance allocator where when a linear memory is reused for another instance the initial heap snapshot of the prior instance can be visible, erroneously to the next instance. This bug has been patched and users should upgrade to Wasmtime 2.0.2 and 1.0.2. Other mitigations include disabling the pooling allocator and disabling the `memory-init-cow`.

Key dates

02Disclosure timeline

November 10, 2022 CVE published
May 2, 2025 Record updated