GHSA-gmw6-94gg-2rc2
HIGHUNIX Symbolic Link (Symlink) Following in @npmcli/arborist
EPSS Exploitation Probability
EPSS (Exploit Prediction Scoring System) is a daily probability model maintained by FIRST.org. It estimates the likelihood a CVE will be exploited in production environments within the next 30 days, derived from real-world threat intelligence signals.
Blast Radius
Weekly download volume for affected packages — a proxy for how broadly this vulnerability is deployed.
@npmcli/arboristnpmDescription
Impact
Arbitrary File Creation, Arbitrary File Overwrite, Arbitrary Code Execution
@npmcli/arborist, the library that calculates dependency trees and manages the node_modules folder hierarchy for the npm command line interface, aims to guarantee that package dependency contracts will be met, and the extraction of package contents will always be performed into the expected folder.
This is accomplished by extracting package contents into a project's node_modules folder.
If the node_modules folder of the root project or any of its dependencies is somehow replaced with a symbolic link, it could allow Arborist to write package dependencies to any arbitrary location on the file system.
Note that symbolic links contained within package artifact contents are filtered out, so another means of creating a node_modules symbolic link would have to be employed.
- A
preinstallscript could replacenode_moduleswith a symlink. (This is prevented by using--ignore-scripts.) - An attacker could supply the target with a git repository, instructing them to run
npm install --ignore-scriptsin the root. This may be successful, becausenpm install --ignore-scriptsis typically not capable of making changes outside of the project directory, so it may be deemed safe.
Patches
2.8.2 (included in npm v7.20.7 and above)
Workarounds
Do not run npm install on untrusted codebases, without first ensuring that the node_modules directory in the project is not a symbolic link.
Fix
Prior to extracting any package contents, the node_modules folder into which it is extracted is verified to be a real directory. If it is not, then it is removed.
Caveat: if you are currently relying on creating a symbolic link to the node_modules folder in order to share dependencies between projects, then that will no longer be possible. Please use the npm link command, explicit file:... dependencies, and/or workspaces to share dependencies in a development environment.
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 📦npm | @npmcli/arborist | all versions | 2.8.2 |
Detection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for @npmcli/arborist. 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 @npmcli/arborist to 2.8.2 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms GHSA-gmw6-94gg-2rc2 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-gmw6-94gg-2rc2 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-gmw6-94gg-2rc2. 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-gmw6-94gg-2rc2 in your dependencies?
O3 detects GHSA-gmw6-94gg-2rc2 across npm dependencies and uses function-level reachability to confirm whether the vulnerable code path is actually reachable — not just present. No false positives.