pnpm is a package manager. Prior to 10.34.5 and from 11.0.0 until 11.11.0, pnpm parses the package name from attacker-controlled pnpm-lock.yaml packages keys with dp.parse(depPath).name and uses it without validation in deps/graph-builder/src/lockfileToDepGraph.ts and pnpm11/deps/graph-builder/src/lockfileToDepGraph.ts. The name reaches path.join(modules, pkgName), storeController.importPackage, and pnpm11/lockfile/to-pnp/src/index.ts, allowing package contents to be written outside node_modules when a user runs pnpm install. When dangerouslyAllowAllBuilds or a matching allowBuilds entry permits lifecycle scripts, the escaped package can execute code with the user's privileges. This issue is fixed in versions 10.34.5 and 11.11.0.

A path traversal vulnerability exists in pnpm package manager versions prior to 10.34.5 and from 11.0.0 until 11.11.0. The flaw stems from pnpm parsing package names from attacker-controlled pnpm-lock.yaml files without proper validation. The unvalidated package name is passed to path.join(), storeController.importPackage, and related functions, enabling package contents to be written outside the intended node_modules directory. If lifecycle scripts are permitted via dangerouslyAllowAllBuilds or a matching allowBuilds configuration, an attacker can achieve arbitrary code execution with the victim user's privileges. The attack vector requires a user to run pnpm install against a malicious or compromised lockfile. This represents a supply chain risk, particularly in CI/CD environments or shared repositories. Fixes are available in pnpm versions 10.34.5 and 11.11.0.