Use After Free Affecting wasmtime-environ package, versions >=43.0.0 <43.0.1
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Test your applications- Snyk IDSNYK-RUST-WASMTIMEENVIRON-15967233
- published10 Apr 2026
- disclosed9 Apr 2026
- creditUnknown
Introduced: 9 Apr 2026
NewCVE-2026-34983 (opens in a new tab)Common Vulnerabilities and Exposures (CVE) are common identifiers for publicly known security vulnerabilities
Common Weakness Enumeration (CWE) is a category system for software weaknesses
How to fix?
Upgrade wasmtime-environ to version 43.0.1 or higher.
Overview
wasmtime-environ is a Standalone environment support for WebAssembly code in Cranelift
Affected versions of this package are vulnerable to Use After Free in the wasmtime::Linker. An attacker can cause unpredictable program behavior and potentially disrupt service by cloning and then dropping a wasmtime::Linker instance before its cloned counterpart is used.