CVE-2026-6410: @fastify/static Path Traversal Vulnerability

MODERATE
Advisory Identifier: GHSA-pr96-94w5-mx2h
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CVSS 5.3
CWE-22
Published
Advisory Summary

CVE-2026-6410 is a MODERATE (CVSS 5.3) path traversal vulnerability (CWE-22: Improper Limitation of a Pathname to a Restricted Directory ('Path Traversal')) affecting @fastify/static libraries in the npm ecosystem. The issue involves @fastify/static vulnerable to path traversal in directory listing. Remediation is available by upgrading affected packages to version 9.1.1.

CVE-2026-6410 at a Glance

CVE Identifier CVE-2026-6410
GHSA Identifier GHSA-pr96-94w5-mx2h
Severity MODERATE
CVSS v3.1 Base Score 5.3
CWE Classification CWE-22: Improper Limitation of a Pathname to a Restricted Directory ('Path Traversal')
Affected Product @fastify/static
Package Ecosystem npm
Published Date
Last Updated

Security Impact

CVSS: 5.3

The security impact metrics below are parsed directly from the CVSS v3.1 vector string (CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N).

Attack Vector Network (AV:N)
Attack Complexity Low (AC:L)
Privileges Required None (PR:N)
User Interaction None (UI:N)
Scope Unchanged (S:U)
Confidentiality Low (C:L)
Integrity None (I:N)
Availability None (A:N)

How to Fix CVE-2026-6410

To remediate this vulnerability, upgrade all affected @fastify/static dependencies to a patched release. Both direct and transitive dependencies should be checked, as frameworks or security libraries may pull in vulnerable versions transitively.

@fastify/static fixed: 9.1.1 
npm install @fastify/static@9.1.1
Verify Direct and Transitive Dependencies

Run the following command in your project directory to verify that all resolved dependencies use the patched release: 

npm ls @fastify/static

How to Check if You Are Affected

To determine whether your Node.js application is affected by CVE-2026-6410, inspect your project dependencies using npm:

npm ls @fastify/static

Analyze the terminal output to locate any version of @fastify/static in your dependency tree. If any resolved version matches the vulnerable ranges listed in the table below (for example, versions earlier than 9.1.1), your application is affected.

Note: The npm ls @fastify/static command inspects dependencies declared in your package.json and lockfile; it does not perform automated runtime dynamic scanning.

Technical Details

Vulnerability Mechanism & Technical Analysis

This vulnerability is classified under CWE-22: Improper Limitation of a Pathname to a Restricted Directory ('Path Traversal'), where the product uses external input to construct a pathname that is intended to identify a file or directory that is located underneath a restricted parent directory, but the product does not properly neutralize special elements within the pathname that can cause the pathname to resolve to a location that is outside of the restricted directory. In @fastify/static, software state validation or input boundaries are circumvented during processing. Review the official source advisory statement below for specific affected components, classes, and reproduction details.

Source Advisory Statement

### Impact `@fastify/static` v9.1.0 and earlier serves directory listings outside the configured static root when the `list` option is enabled. A request such as `/public/../outside/` causes `dirList.path()` to resolve a directory outside the root via `path.join()` without a containment check. A remote unauthenticated attacker can obtain directory listings for arbitrary directories accessible to the Node.js process, disclosing directory names and filenames that should not be exposed. File contents are not disclosed. ### Patches Upgrade to `@fastify/static` >= 9.1.1. ### Workarounds Disable directory listing by removing the `list` option from the plugin configuration.

CVE-2026-6410 Affected @fastify/static Versions

1 component(s)
Fixed Versions:
9.1.1
Product / Package Ecosystem Affected Versions Fixed Version
@fastify/static
npm/@fastify/static
npm
≥ 8.0.0
< 9.1.1
9.1.1

References

GitHub Advisory / Wiki ADVISORY
https://github.com/fastify/fastify-static/security/advisories/GHSA-pr96-94w5-mx2h
NVD — CVE-2026-6410 NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-6410
@fastify/static Security Information SECURITY
https://cna.openjsf.org/security-advisories.html
@fastify/static Source Repository REPOSITORY
https://github.com/fastify/fastify-static

Frequently Asked Questions

What is CVE-2026-6410?
CVE-2026-6410 is a security vulnerability in @fastify/static involving @fastify/static vulnerable to path traversal in directory listing under CWE-22: Improper Limitation of a Pathname to a Restricted Directory ('Path Traversal').
Which @fastify/static versions are affected?
Affected versions include releases prior to 9.1.1 across affected packages: @fastify/static.
What version fixes CVE-2026-6410?
Upgrading to 9.1.1 (or the latest patched release for your respective branch) resolves the vulnerability.
Is @fastify/static affected?
Yes, @fastify/static is affected in releases prior to 9.1.1. Upgrade your dependency to 9.1.1 or later.
What is the CVSS score of CVE-2026-6410?
CVE-2026-6410 has a CVSS v3.1 base score of 5.3 (MODERATE) with vector string CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N.
What CWE is associated with CVE-2026-6410?
CVE-2026-6410 is classified under CWE-22: Improper Limitation of a Pathname to a Restricted Directory ('Path Traversal') (The product uses external input to construct a pathname that is intended to identify a file or directory that is located underneath a restricted parent directory, but the product does not properly neutralize special elements within the pathname that can cause the pathname to resolve to a location that is outside of the restricted directory.).
How can I check npm dependencies for CVE-2026-6410?
Run the dependency tree command: 'npm ls @fastify/static'. This command lists direct and transitive dependencies in your build configuration so you can verify if a vulnerable version is resolved.
Machine-readable OSV JSON OSV v1.5 Schema
Normalized schema output
View Raw JSON 
{
  "schema_version" : "1.4.0",
  "id" : "GHSA-pr96-94w5-mx2h",
  "modified" : "2026-04-16T22:34:30Z",
  "published" : "2026-04-16T22:34:30Z",
  "aliases" : [ "CVE-2026-6410" ],
  "summary" : "@fastify/static vulnerable to path traversal in directory listing",
  "details" : "### Impact\n\n`@fastify/static` v9.1.0 and earlier serves directory listings outside the configured static root when the `list` option is enabled. A request such as `/public/../outside/` causes `dirList.path()` to resolve a directory outside the root via `path.join()` without a containment check.\n\nA remote unauthenticated attacker can obtain directory listings for arbitrary directories accessible to the Node.js process, disclosing directory names and filenames that should not be exposed. File contents are not disclosed.\n\n### Patches\n\nUpgrade to `@fastify/static` >= 9.1.1.\n\n### Workarounds\n\nDisable directory listing by removing the `list` option from the plugin configuration.",
  "severity" : [ {
    "type" : "CVSS_V3",
    "score" : "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N"
  } ],
  "affected" : [ {
    "package" : {
      "ecosystem" : "npm",
      "name" : "@fastify/static"
    },
    "ranges" : [ {
      "type" : "ECOSYSTEM",
      "events" : [ {
        "introduced" : "8.0.0"
      }, {
        "fixed" : "9.1.1"
      } ]
    } ],
    "database_specific" : {
      "last_known_affected_version_range" : "<= 9.1.0"
    }
  } ],
  "references" : [ {
    "type" : "WEB",
    "url" : "https://github.com/fastify/fastify-static/security/advisories/GHSA-pr96-94w5-mx2h"
  }, {
    "type" : "ADVISORY",
    "url" : "https://nvd.nist.gov/vuln/detail/CVE-2026-6410"
  }, {
    "type" : "WEB",
    "url" : "https://cna.openjsf.org/security-advisories.html"
  }, {
    "type" : "PACKAGE",
    "url" : "https://github.com/fastify/fastify-static"
  } ],
  "database_specific" : {
    "cwe_ids" : [ "CWE-22" ],
    "severity" : "MODERATE",
    "github_reviewed" : true,
    "github_reviewed_at" : "2026-04-16T22:34:30Z",
    "nvd_published_at" : "2026-04-16T14:16:20Z"
  }
}