GHSA-859w-5945-r5v3
Vite's server.fs.deny bypassed with /. for files under project root
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.
vitenpmDescription
Summary
The contents of files in the project root that are denied by a file matching pattern can be returned to the browser.
Impact
Only apps explicitly exposing the Vite dev server to the network (using --host or server.host config option) are affected.
Only files that are under project root and are denied by a file matching pattern can be bypassed.
- Examples of file matching patterns:
.env,.env.*,*.{crt,pem},**/.env - Examples of other patterns:
**/.git/**,.git/**,.git/**/*
Details
server.fs.deny can contain patterns matching against files (by default it includes .env, .env.*, *.{crt,pem} as such patterns).
These patterns were able to bypass for files under root by using a combination of slash and dot (/.).
PoC
npm create vite@latest
cd vite-project/
cat "secret" > .env
npm install
npm run dev
curl --request-target /.env/. http://localhost:5173
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 📦npm | vite | ≥ 6.3.0&&< 6.3.4 | 6.3.4 |
| 📦npm | vite | ≥ 6.2.0&&< 6.2.7 | 6.2.7 |
| 📦npm | vite | ≥ 6.0.0&&< 6.1.6 | 6.1.6 |
| 📦npm | vite | ≥ 5.0.0&&< 5.4.19 | 5.4.19 |
| 📦npm | vite | all versions | 4.5.14 |
Detection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for vite. 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 vite to 6.3.4 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms GHSA-859w-5945-r5v3 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-859w-5945-r5v3 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-859w-5945-r5v3. 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-859w-5945-r5v3 in your dependencies?
O3 detects GHSA-859w-5945-r5v3 across npm dependencies and uses function-level reachability to confirm whether the vulnerable code path is actually reachable — not just present. No false positives.