CVE-2024-23331: Vite dev server option `server.fs.deny` can be bypassed when hosted on case-insensitive filesystem

Severity: high (CVSS 7.5 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 0.8% probability of exploitation in the next 30 days
Public exploit or detection template: yes
Published: 2024-01-19 · updated 2026-06-17
Weakness: CWE-178

Description

Vite is a frontend tooling framework for javascript. The Vite dev server option `server.fs.deny` can be bypassed on case-insensitive file systems using case-augmented versions of filenames. Notably this affects servers hosted on Windows. This bypass is similar to CVE-2023-34092 -- with surface area reduced to hosts having case-insensitive filesystems. Since `picomatch` defaults to case-sensitive glob matching, but the file server doesn't discriminate; a blacklist bypass is possible. By requesting raw filesystem paths using augmented casing, the matcher derived from `config.server.fs.deny` fails to block access to sensitive files. This issue has been addressed in vite@5.0.12, vite@4.5.2, vite@3.2.8, and vite@2.9.17. Users are advised to upgrade. Users unable to upgrade should restrict access to dev servers.

Affected products

vitejs vite: from 2.7.0 before 2.9.17; from 3.0.0 before 3.2.8; from 4.0.0 before 4.5.2; from 5.0.0 before 5.0.12 — fixed in 2.9.17, 3.2.8, 4.5.2, 5.0.12

How to fix

Upgrade to a fixed version: vitejs vite 2.9.17, 3.2.8, 4.5.2, 5.0.12. Check the vendor advisory for mitigations.

References

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