---
id: CVE-2026-90982
title: >-
  @fastify/static is a Fastify plugin that serves static files from a configured
  root directory
summary: >-
  @fastify/static is a Fastify plugin that serves static files from a configured
  root directory. In versions before 10.1.4, on a case-insensitive filesystem
  such as Windows or the default macOS volume, a route guard or allowedPath
  restrict…
severity: medium
cvss: 5.3
cvssVector: 'CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N'
cwe:
  - CWE-178
  - CWE-284
vendor: '@fastify/static'
product: '@fastify/static'
affected:
  - '@fastify/static < 10.1.4'
published: '2026-09-17'
updated: '2026-09-18'
sourceUpdated: '2026-09-18T19:07:38.320'
source: NVD
sourceUrl: 'https://nvd.nist.gov/vuln/detail/CVE-2026-90982'
references:
  - url: 'https://cna.openjsf.org/security-advisories.html'
    label: ce714d77-add3-4f53-aff5-83d477b104bb
  - url: >-
      https://github.com/fastify/fastify-static/security/advisories/GHSA-r799-r9gc-m956
    label: ce714d77-add3-4f53-aff5-83d477b104bb
  - url: >-
      https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-90982.json
  - url: 'https://access.redhat.com/security/cve/CVE-2026-90982'
  - url: 'https://bugzilla.redhat.com/show_bug.cgi?id=2535831'
  - url: 'https://www.cve.org/CVERecord?id=CVE-2026-90982'
  - url: 'https://nvd.nist.gov/vuln/detail/CVE-2026-90982'
tags:
  - nvd
  - cve.org
  - csaf
  - vex
  - red-hat
epss: 0.00585
epssPercentile: 0.45763
ssvc:
  exploitation: none
  automatable: 'yes'
  technicalImpact: partial
  timestamp: '2026-09-17T12:32:46.853799Z'
ingestedAt: '2026-09-17T07:13:35.793Z'
---

## Overview

@fastify/static is a Fastify plugin that serves static files from a configured root directory. In versions before 10.1.4, on a case-insensitive filesystem such as Windows or the default macOS volume, a route guard or allowedPath restriction can be bypassed by altering the letter case of a path segment. The route matcher is case-sensitive while the filesystem is not, so a request that changes the case of a protected segment does not match the guarded route and falls through to the static handler, yet the filesystem resolves it to the same protected file. As a result, an unauthenticated request can read a file that a route guard or allowedPath was configured to protect. The issue does not affect case-sensitive filesystems and is not a directory traversal, since nothing is served from outside the configured root. The issue is fixed in @fastify/static 10.1.4, which validates the requested path against its actual on-disk spelling and rejects case-aliased paths before authorization. As a workaround, serve static files from a case-sensitive filesystem, or ensure route guards and allowedPath rules account for every letter-case variant of the protected paths.

## Remediation

Refer to the linked advisories for vendor-supplied fixes and affected version ranges.

## Vendor advisories

- **Red Hat VEX** · Moderate · updated 2026-09-18 · [vex](https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-90982.json)