CVE-2025-62522
vite allows server.fs.deny bypass via backslash on Windows
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
Vite is a frontend tooling framework for JavaScript. In versions from 2.9.18 to before 3.0.0, 3.2.9 to before 4.0.0, 4.5.3 to before 5.0.0, 5.2.6 to before 5.4.21, 6.0.0 to before 6.4.1, 7.0.0 to before 7.0.8, and 7.1.0 to before 7.1.11, files denied by server.fs.deny were sent if the URL ended with \ when the dev server is running on Windows. Only apps explicitly exposing the Vite dev server to the network and running the dev server on Windows were affected. This issue has been patched in versions 5.4.21, 6.4.1, 7.0.8, and 7.1.11.
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 📦npm | vite | ≥ 7.1.0&&< 7.1.11 | 7.1.11 |
| 📦npm | vite | ≥ 7.0.0&&< 7.0.8 | 7.0.8 |
| 📦npm | vite | ≥ 6.0.0&&< 6.4.1 | 6.4.1 |
| 📦npm | vite | ≥ 2.9.18&&< 5.4.21 | 5.4.21 |
| 📦npm | vite | ≥ 3.2.9&&< 5.4.21 | 5.4.21 |
| 📦npm | vite | ≥ 4.5.3&&< 5.4.21 | 5.4.21 |
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 7.1.11 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2025-62522 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 CVE-2025-62522 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 CVE-2025-62522. Runtime protection reduces exposure until a permanent patch is applied and verified — it complements patching, it doesn't replace it.
Frequently Asked Questions
Is CVE-2025-62522 in your dependencies?
O3 detects CVE-2025-62522 across npm dependencies and uses function-level reachability to confirm whether the vulnerable code path is actually reachable — not just present. No false positives.