title: Wasmtime vulnerable to data leakage between instances in the pooling allocator
description: Wasmtime is a standalone runtime for WebAssembly. Prior to version 2.0.2, 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. Other mitigations include disabling the pooling allocator and disabling the `memory-init-cow`.
problem types: CWE-226: Sensitive Information in Resource Not Removed Before Reuse
affected:
{
vendor: bytecodealliance
product: wasmtime
versions:
version: < 2.0.2, status: affected
}
metrics:
cvssV3_1: [
version: 3.1
vectorString: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:N/A:N
attackVector: NETWORK
attackComplexity: LOW
privilegesRequired: NONE
userInteraction: NONE
scope: CHANGED
confidentialityImpact: HIGH
integrityImpact: NONE
availabilityImpact: NONE
baseScore: 8.6
baseSeverity: HIGH
]