GHSA-pr96-94w5-mx2h — medium GitHub Advisory (CVE-2026-6410) in npm/@fastify/static

Description

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.

Basic information

Type: reviewed
Severity: medium
Advisory on GitHub: Open advisory ↗
Repository advisory: Open repository advisory ↗
Source code: Browse source ↗
Published (advisory): 2026-04-16 22:34:30 UTC
Updated: 2026-04-16 22:34:31 UTC
GitHub reviewed: 2026-04-16 22:34:30 UTC
NVD published: 2026-04-16

Score	Percentile
0.02%	4.19%

CVSS Scores

Base score	Version	Severity	Vector
5.3	3.1	—	`CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N` Click to expand Attack vector (AV:N) Could be attacked over the internet or any normal routed network—not just someone sitting at the machine. Attack complexity (AC:L) Once they can reach the bug, pulling it off is straightforward—no weird race conditions or rare setup. Privileges required (PR:N) No account or special rights needed—anonymous or random user is enough. User interaction (UI:N) Nobody has to click “OK” or open a trap file; it can work without a victim helping. Scope (S:U) Damage stays in the same “trust bubble” as the broken component—no big spill into unrelated systems. Confidentiality (C:L) Some sensitive info could get out, but not a total data dump. Integrity (I:N) Data isn’t meaningfully altered or forged. Availability (A:N) Service keeps running; no real outage angle.

Identifiers

Type	Value
GHSA	GHSA-pr96-94w5-mx2h ↗
CVE	CVE-2026-6410 ↗

CWEs

CWE id	Name
CWE-22	Improper Limitation of a Pathname to a Restricted Directory ('Path Traversal')

Credits

yuki-matsuhashi (finder)
mcollina (remediation_developer)
UlisesGascon (remediation_reviewer)
climba03003 (remediation_reviewer)

Affected packages (1)

Vulnerable version ranges and first patched releases as published by GitHub.

Ecosystem	Package	Vulnerable range	First patched	Vulnerable functions
npm	@fastify/static	>= 8.0.0, <= 9.1.0	9.1.1	—

@fastify/static vulnerable to path traversal in directory listing