How severe is CVE-2026-53571?

No CVSS score has been assigned to CVE-2026-53571 yet. Review the advisory details and affected package list to assess your exposure.

Which packages are affected by CVE-2026-53571?

CVE-2026-53571 affects the following packages: vite (npm), vite (npm), vite (npm), vite-plus (npm). Ecosystems affected: npm.

How do I fix CVE-2026-53571?

Update vite to 8.0.16 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2026-53571 is resolved across your whole dependency graph.

How do I detect CVE-2026-53571 in my npm dependencies?

Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for vite, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.

How do I mitigate CVE-2026-53571 if there is no patch (or I can't update yet)?

Resolve every user-supplied path to its canonical form and reject anything that escapes the intended directory, and run the component under an account that has no read or write access outside the directory it legitimately serves.

Is CVE-2026-53571 actively exploited in the wild?

No public exploit code has been indexed for CVE-2026-53571 yet. This does not mean the vulnerability cannot be exploited — absence of public exploits does not imply safety. Apply the recommended fix and use O3 Security to monitor your exposure.

What is the EPSS score for CVE-2026-53571?

CVE-2026-53571 has an EPSS (Exploit Prediction Scoring System) score of 0.6%, placing it in the 47th percentile of all CVEs. EPSS is maintained by FIRST.org and estimates the probability that a vulnerability will be exploited in the wild within the next 30 days. This score indicates relatively lower exploitation probability, though the CVSS severity should still guide your patching priority.

What type of vulnerability is CVE-2026-53571?

CVE-2026-53571 is classified as Path Traversal (CWE-22), Information Exposure (CWE-200). These weakness types describe the underlying flaw category, which helps determine the potential impact and the right class of mitigation. This is a high-impact weakness class that often enables remote code execution or data exposure.

When was CVE-2026-53571 published, and has it been updated?

CVE-2026-53571 was published on June 22, 2026 and was last updated on October 24, 2026. Advisory data evolves as severity scores, affected ranges, and exploit intelligence are revised — always check the latest version of the advisory before acting.

📦 npm

Not in CISA KEV

CVE-2026-53571 — vite

CVE-2026-53571 is a Path Traversal vulnerability in vite. A fix is available for vite — see the affected versions and patch details below.

Vite: `server.fs.deny` bypass on Windows alternate paths

Also known asGHSA-fx2h-pf6j-xcff

Published

Jun 22, 2026

Updated

Oct 24, 2026

Affected

4 pkgs

Patched

4 / 4

Exploits

None indexed

Exploitation data as of Oct 23, 2026 · OSV.dev, NVD, FIRST.org (EPSS)

Exploitation Status

Proof-of-concept exploit code exists

CISA’s SSVC triage found public proof-of-concept exploit code for this CVE, though no confirmed active exploitation.

Exploitation and automatability from CISA’s SSVC triage for CVE-2026-53571.

EPSS Exploitation Probability

via FIRST.org ↗

0.6%probability of exploitation in next 30 days

Lower Risk0.00%

Lower risk than most CVEs47th percentile — riskier than 47% of all scored CVEsHighest risk

Probability of exploitation in the next 30 days, from FIRST.org EPSS.

Real-World Exposure

4 pkgs affected

How broadly this vulnerability is actually deployed: weekly install volume shows current usage, and reverse-dependency count shows how many other packages break if it stays unpatched.

7Kother npm packages depend on this — each one inherits the vulnerability until it's patched upstream

vitenpm

127.2Mdownloads / week

Description

Summary

The contents of files that are specified by server.fs.deny can be returned to the browser on Windows.

Impact

Only apps that match the following conditions are affected:

explicitly exposes the Vite dev server to the network (using --host or server.host config option)
the sensitive file exists in the allowed directories specified by server.fs.allow
either of:
- the sensitive file exists in an NTFS volume
- the dev server is running on Windows and the sensitive file exists in a volume that 8.3 short name generation is enabled (it is enabled by default on system volumes)

Details

Vite’s dev server denies direct access to sensitive files through server.fs.deny, including entries such as .env, .env.*, and *.{crt,pem}. However, on Windows, the deny logic does not correctly normalize NTFS ADS path forms before access checks are applied. Because of this, requests such as /.env::$DATA?raw are treated as allowed paths, while Windows resolves them to the original file's default data stream.

Similar to that, Windows allows accessing a file using a different name with the 8.3 short name compatibility feature. Vite did not reject accessing files via them.

PoC

$ npm create vite@latest
$ cd vite-project/
$ npm install
$ npm run dev

Access via browser at http://localhost:5173/.env::$DATA?raw <img width="388" height="129" alt="deecc1315123883cfd0f9c26a002845a" src="https://github.com/user-attachments/assets/895c6012-4e2e-4a35-babb-69bbf3ee7170" />

Example expected result:

/.env::$DATA?raw returns the contents of .env
/tls.pem::$DATA?raw returns the contents of tls.pem

Affected Packages

4 total 4 fixed

Ecosystem	Package	Vulnerable range	Fix
📦npm	`vite`	≥ 8.0.0&&< 8.0.16	8.0.16`npm install vite@8.0.16`
📦npm	`vite`	≥ 7.0.0&&< 7.3.5	7.3.5`npm install vite@7.3.5`
📦npm	`vite`	all versions	6.4.3`npm install vite@6.4.3`
📦npm	`vite-plus`	all versions	0.1.24`npm install vite-plus@0.1.24`

Affected Products

2 products · 4 configurations

Application

vitevitejs

≥ 8.0.0 && < 8.0.16

range

Application

vite\+voidzero

< 0.1.24

range

Detection & mitigation playbook

Open-source dependency

Detect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for vite, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.
Fix
Update vite to 8.0.16 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2026-53571 is resolved across your whole dependency graph.
Workarounds
Resolve every user-supplied path to its canonical form and reject anything that escapes the intended directory, and run the component under an account that has no read or write access outside the directory it legitimately serves.

Frequently Asked Questions

### Summary The contents of files that are specified by [`server.fs.deny`](https://vite.dev/config/server-options#server-fs-deny) can be returned to the browser on Windows. ### Impact Only apps that match the following conditions are affected: - explicitly exposes the Vite dev server to the network (using `--host` or [`server.host` config option](https://vitejs.dev/config/server-options.html#server-host)) - the sensitive file exists in the allowed directories specified by [`server.fs.allow`](https://vite.dev/config/server-options#server-fs-allow) - either of: - the sensitive file exists

O3 Security · Impact-Aware SCA

Is CVE-2026-53571 in your dependencies?

Find it across npm, including transitive dependencies.

Scan my dependencies How O3 SCA works