Nuxt dev server vite-node IPC socket is world-connectable on LinuxGHSA-534h-c3cw-v3h9
MEDIUMFix: nuxt/nuxt@1f9f476GHSA-534h-c3cw-v3h9 is a medium-severity (CVSS 5.5) Incorrect Default Permissions vulnerability in nuxt. A fix is available for nuxt — see the affected versions and patch details below.
Exploitation Status
No confirmed exploitation observed yet
- CISA’s own triage has not observed active exploitation or public proof-of-concept code for this CVE as of its last assessment.
Exploitation and automatability from CISA’s SSVC triage for GHSA-534h-c3cw-v3h9.
EPSS Exploitation Probability
Probability of exploitation in the next 30 days, from FIRST.org EPSS.
How urgent is this, really
GHSA-534h-c3cw-v3h9 by exploitation likelihood (EPSS) against impact (CVSS). Outside the shaded patch-first corner.
Where this sits among everything scored
Of 383,485 CVEs with a current EPSS score, this one falls in the < 10% band (highlighted). Counts from FIRST.org, log-scaled.
Real-World Exposure
How broadly this vulnerability is actually deployed: weekly install volume shows current usage, and reverse-dependency count shows how many other packages break if it stays unpatched.
nuxtnpmDescription
Impact
When running nuxt dev on Linux (Node.js 20+, outside Docker / StackBlitz), Nuxt's internal vite-node IPC server binds to a Linux abstract-namespace Unix socket (\0nuxt-vite-node-<pid>-<ts>.sock). Abstract sockets have no filesystem inode and therefore no permission bits: any local UID on the host that can read /proc/net/unix can enumerate the socket and connect to it.
The IPC server does not perform any peer-credential or shared-secret check before dispatching requests. The module request type passes its moduleId field straight into Vite's SSR fetchModule(), which is not gated by Vite's HTTP-layer server.fs.allow deny-list. A co-resident unprivileged local user can therefore request paths like /home/<dev>/project/.env?raw or ~/.ssh/id_rsa?raw and read the developer's secrets through the dev server's SSR plugin pipeline. The resolve request type additionally enables filesystem probing.
This affects developers running nuxt dev on shared multi-tenant Linux hosts (lab machines, shared bastions, CI runners shared between jobs without per-job container isolation). It does not affect:
- Production builds (
nuxt build/nuxt start). The IPC server only runs in development. - macOS or Windows developers.
- Docker / StackBlitz environments, which already fall back to a filesystem socket.
- Single-user laptops or per-job containerised CI.
Patches
Fixed in [email protected] (commit 1f9f4767) and backported to [email protected] (commit c293bf95).
The fix removes the abstract-namespace branch entirely. The IPC server now always binds to a filesystem Unix socket under the OS temp directory and explicitly chmod 0600s it after listen(), restricting connections to the owning UID. If the chmod fails for any reason, the server closes rather than serve requests on an unrestricted channel.
Workarounds
If you cannot upgrade immediately on an affected host:
- Run
nuxt devinside a container or VM with no other tenants. Docker already triggers the filesystem-socket fallback in vulnerable versions and that fallback is unaffected. - Bind the dev process to a single-user namespace (
unshare -U, rootless containers). - Restrict
/proc/net/unixvisibility viahidepid=2mount options where applicable, though this is partial mitigation only.
References
- Affected file:
packages/vite/src/plugins/vite-node.ts - CWE-276: Incorrect Default Permissions
Credit
Reported by Anthropic / Claude as part of Anthropic's coordinated vulnerability disclosure programme, reference ANT-2026-MSNKZFAT. Thanks to the Anthropic security team for the report and the detailed reproduction.
Independently reported by @alcls01111 via GitHub's coordinated disclosure flow (GHSA-5gvc-46gq-948j), closed as a duplicate of this advisory.
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 📦npm | nuxt | ≥ 4.0.0&&< 4.4.7 | 4.4.7npm install nuxt@4.4.7 |
| 📦npm | nuxt | ≥ 3.18.0&&< 3.21.7 | 3.21.7npm install nuxt@3.21.7 |
Affected Products
nuxtnuxtDetection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for nuxt, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.
Fix
Update nuxt to 4.4.7 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms GHSA-534h-c3cw-v3h9 is resolved across your whole dependency graph.
Workarounds
Close the privilege gap rather than the entry point: audit which accounts, roles and service identities can reach the affected operation, drop the component to the least privilege it actually needs, and review file and directory permissions created by earlier installs — a default left in place is what makes this reachable.
Frequently Asked Questions
Is GHSA-534h-c3cw-v3h9 in your dependencies?
Find it across npm, including transitive dependencies.