A path traversal flaw in pnpm allows an attacker to create a symbolic link that points outside the intended node_modules/.pnpm-config directory. The vulnerability arises when pnpm processes the configDependencies section of a pnpm-lock.yaml file, using the listed package names directly to construct the symlink destination. The likely attack vector is the execution of pnpm install on a repository containing a maliciously crafted lockfile; based on the description, it is inferred that the attacker must supply the lockfile and that the executing user has write permission to the target directory.

The flaw affects all users running pnpm prior to version 10.34.4 or 11.8.0. Developers, CI/CD pipelines, and any environment that installs packages from potentially untrusted repositories using these older pnpm releases are impacted. The problem manifests during the pnpm install command when the lockfile is parsed.

The CVSS score of 8.2 signals a high severity, while the EPSS score of < 1% indicates a very low probability of widespread exploitation. The vulnerability is not listed in the CISA KEV catalog. Successful exploitation requires a malicious pnpm-lock.yaml file and write access to the project directory; the attacker can then create a symlink to an arbitrary target within the user’s filesystem, potentially redirecting package resolution or affecting subsequent build steps.