yeoman-environment Vulnerable to Arbitrary Package Installation without User Confirmation
Date: 2026-05
Affected: npm/yeoman-environment
Attack vector: rce
Category: vulnerability-disclosure
Severity: High
CVE: CVE-2026-42089
CWE: CWE-829
CVSS: 8.6 (CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:C/C:H/I:H/A:H)

### Impact `yeoman-environment` versions `>= 2.9.0` and `< 6.0.1` install missing local generator packages from caller-supplied package names without user confirmation. In downstream consumers that pass attacker-controlled project configuration into this path, this can result in arbitrary package installation and code execution during CLI bootstrap. The vulnerable method is `installLocalGenerators()`, which calls `repository.install()` directly without prompting the user. ### Patches Upgrade to `yeoman-environment` `6.0.1`, which adds an interactive confirmation prompt before installation ([PR #753](https://github.com/yeoman/environment/pull/753)). ### Workarounds None. ### Resources - [Fix commit 78d2af7](https://github.com/yeoman/environment/commit/78d2af7e60294784b8a8b3b3b5099c6874b6a1fa)


Mitigations:

Architectural layers (MAESTRO):