GHSA-v253-rj99-jwpq
Fix: pnpm/pnpm@17432adGHSA-v253-rj99-jwpq is a Path Traversal vulnerability in pnpm. O3 Security confirms whether GHSA-v253-rj99-jwpq is actually reachable in your code before you act, and blocks exploitation at runtime until you patch.
pnpm has Path Traversal via arbitrary file permission modification
Real-World Exposure
How broadly this vulnerability is actually deployed: weekly install volume shows current usage, a proxy for how much of the ecosystem is exposed.
pnpmnpmDescription
Summary
When pnpm processes a package's directories.bin field, it uses path.join() without validating the result stays within the package root. A malicious npm package can specify "directories": {"bin": "../../../../tmp"} to escape the package directory, causing pnpm to chmod 755 files at arbitrary locations.
Note: Only affects Unix/Linux/macOS. Windows is not affected (fixBin gated by EXECUTABLE_SHEBANG_SUPPORTED).
Details
Vulnerable code in pkg-manager/package-bins/src/index.ts:15-21:
if (manifest.directories?.bin) {
const binDir = path.join(pkgPath, manifest.directories.bin) // NO VALIDATION
const files = await findFiles(binDir)
// ... files outside package returned, then chmod 755'd
}
The bin field IS protected with isSubdir() at line 53, but directories.bin lacks this check.
PoC
# Create malicious package
mkdir /tmp/malicious-pkg
echo '{"name":"malicious","version":"1.0.0","directories":{"bin":"../../../../tmp/target"}}' > /tmp/malicious-pkg/package.json
# Create sensitive file
mkdir -p /tmp/target
echo "secret" > /tmp/target/secret.sh
chmod 600 /tmp/target/secret.sh # Private
# Install
pnpm add file:/tmp/malicious-pkg
# Check permissions
ls -la /tmp/target/secret.sh # Now 755 (world-readable)
Impact
- Supply-chain attack via npm packages
- File permissions changed from 600 to 755 (world-readable)
- Affects non-dotfiles in predictable paths (dotfiles excluded by tinyglobby default)
Suggested Fix
Add isSubdir validation for directories.bin paths in pkg-manager/package-bins/src/index.ts, matching the existing validation in commandsFromBin():
if (manifest.directories?.bin) {
const binDir = path.join(pkgPath, manifest.directories.bin)
if (!isSubdir(pkgPath, binDir)) {
return [] // Reject paths outside package
}
// ...
}
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 📦npm | pnpm | all versions | 10.28.2 |
Detection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for pnpm. O3's reachability analysis confirms whether the vulnerable code path is actually invoked in your application, so you act on real exposure instead of every transitive match.
Fix
Update pnpm to 10.28.2 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms GHSA-v253-rj99-jwpq is resolved across your whole dependency graph.
Workarounds
If you can't upgrade right away: gate or disable the affected feature, validate untrusted input at the boundary, and avoid passing attacker-controlled data into the vulnerable path. O3's runtime protection blocks exploitation in production as an interim safeguard until the upgrade lands.
How O3 protects you
O3 pinpoints whether GHSA-v253-rj99-jwpq is reachable in your code and exactly where to fix it, then blocks exploitation in production at runtime until the patched version is deployed.
Tailored to GHSA-v253-rj99-jwpq. Runtime protection reduces exposure until a permanent patch is applied and verified — it complements patching, it doesn't replace it.
Frequently Asked Questions
Is GHSA-v253-rj99-jwpq in your dependencies?
O3 detects GHSA-v253-rj99-jwpq across npm dependencies and uses function-level reachability to confirm whether the vulnerable code path is actually reachable — not just present. No false positives.