GHSA-wh6w-3828-g9qf: wasmtime (CVE-2022-39393)

Package	Ecosystem	Affected	Fixed in
wasmtime	crates.io	>=0.0.0-0, <1.0.2 \|\| >=2.0.0, <2.0.2	1.0.2, 2.0.2

Machine-written summary

Summary written by Claude Haiku from the source advisory. Not reviewed by a person.

Wasmtime versions before 1.0.2 and from 2.0.0 before 2.0.2 are affected by a bug in the pooling instance allocator. When a linear memory is reused for a new instance, the initial heap snapshot of the previous instance can be visible to the next instance. The source gives few details on the attacker's required access. Upgrade to Wasmtime 1.0.2 or 2.0.2, depending on the release line in use.

Written 3 Nov 2026.

Not analysed yet

We haven’t published our analysis of this Advisory yet. Once a person has reviewed it, this page will say what’s vulnerable, what has to be true for your app to be affected, and how to check.

Severity and exploitation

Score	Rating	CVSS	Vector	Source
8.6	High	3.1	CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:N/A:N	CNA (GitHub_M)

CISA KEV Not listed.
EPSS 0.0075, the 55th percentile, on 5 Nov 2026: FIRST’s estimate of the chance of exploitation in the next 30 days.

Timeline

31 Oct 2026, 14:24 UTC First seen by agentprime
31 Oct 2026, 14:24 UTC Confirmed by OSV

Sources

Facts on this page come from the GitHub Advisory Database (CC-BY 4.0), OSV and the other sources listed, as published. We don’t reproduce full advisory descriptions, which can contain exploit code.