Vulnerability report

Active exploitation observed Confirmed confidence Not in CISA KEV

CVE-2026-39364

Vite has a `server.fs.deny` bypass with queries

Vitejs / vite · affected before *

View live feed Monitor via API Watch CVE-2026-39364
Severity
CVSS 8.2 · High
Confidence
Confirmed
Exploit status
Observed in sensors
EPSS
2.0%
First observed
14 Jun 2026
Last observed
16 Sep 2026

Decision summary

What security teams need to know first

Direct answers before the deeper technical record.

What it is

CVE-2026-39364 is an unauthenticated Vite has a `server.fs.deny` bypass with queries. Vite is a frontend tooling framework for JavaScript. From 7.1.0 to before 7.3.2 and 8.0.5, on the Vite dev server, files that...

Is it exploited?

Yes. Previdian sensors observed exploitation attempts with confirmed confidence. Also confirmed by third-party sources.

Who is affected?

Vitejs / vite affected before *.

What should we do?

Patch immediately, validate internet-facing exposure, and monitor for matching requests.

Overview

Vite is a frontend tooling framework for JavaScript

Vite is a frontend tooling framework for JavaScript. From 7.1.0 to before 7.3.2 and 8.0.5, on the Vite dev server, files that should be blocked by server.fs.deny (e.g., .env, *.crt) can be retrieved with HTTP 200 responses when query parameters such as ?raw, ?import&raw, or ?import&url&inline are appended.

This vulnerability is fixed in 7.3.2 and 8.0.5.

Red Hat Unaffected
Red Hat Ansible Automation Platform 2.6 ansible-automation-platform-tech-preview/mcp-server-rhel9
Before *
Red Hat Unaffected
Red Hat Advanced Cluster Security 4 rhacs-eng/release-main
All versions (default: unaffected)
Red Hat Affected
Red Hat Ansible Automation Platform 2 automation-controller
All versions (default: affected)
Red Hat Unaffected
Red Hat Ansible Automation Platform 2 automation-eda-controller
All versions (default: unaffected)
Red Hat Unaffected
Red Hat Ansible Automation Platform 2 automation-gateway
All versions (default: unaffected)
Red Hat Unaffected
Red Hat Ansible Automation Platform 2 automation-platform-ui
All versions (default: unaffected)
Red Hat Unaffected
Red Hat Ansible Automation Platform 2 redhat-user-workloads/gateway-rhel9
All versions (default: unaffected)
Red Hat Affected
Red Hat Build of Keycloak vite
All versions (default: affected)
Red Hat Affected
Red Hat Build of Podman Desktop podman-desktop-macos-1-0
All versions (default: affected)
Red Hat Affected
Red Hat Build of Podman Desktop podman-desktop-windows-1-0
All versions (default: affected)
Red Hat Affected
Red Hat Build of Podman Desktop - Tech Preview redhat-user-workloads/bootc-ext
All versions (default: affected)
Red Hat Affected
Red Hat Build of Podman Desktop - Tech Preview redhat-user-workloads/openshift-local-ext
All versions (default: affected)
Red Hat Affected
Red Hat Build of Podman Desktop - Tech Preview redhat-user-workloads/rhel-ext
All versions (default: affected)
Red Hat Unaffected
Red Hat JBoss Enterprise Application Platform 8 vite
All versions (default: unaffected)
Red Hat Affected
Red Hat JBoss Enterprise Application Platform Expansion Pack vite
All versions (default: affected)
Red Hat Affected
Red Hat OpenShift Container Platform 4 redhat-user-workloads/art-images
All versions (default: affected)
vitejs Affected
vite
>= 8.0.0, < 8.0.5 >= 7.1.0, < 7.3.2
vitejs Affected
vite-plus
Before 0.1.16
Published
07 Apr 2026
Exploited Since
14 Jun 2026
Attack vector
Remote
Complexity
Low
Privileges
None
User interaction
None

Tags

nuclei_scanner

CVE References

Exploitation evidence

Why Previdian marks this CVE as exploited

Third-party attestation and first-party sensor observation are shown separately so teams can judge the evidence chain.

Exploited in the wild

TheHackerNews

Recorded 15 Sep 2026

A trusted third party reported exploitation.

Active exploitation observed

Previdian sensor

First observed 15 Sep 2026

Previdian first observed exploitation attempts targeting this vulnerability in our honeypot sensors.

Proof of concept available

Nuclei Templates

Recorded 12 Jun 2026

Public scanner or PoC coverage increases practical exploitability.

Known exploited vulnerability sources

Per-source evidence links for KEV attestations are available through the Previdian Pro API.

Learn about Pro API access
Source Added
TheHackerNews First 2026-09-15 15:40 UTC
Previdian 2026-09-15 16:00 UTC

Operational indicators for this CVE are listed under Detection.

Sensor telemetry

First-party evidence of exploitation activity

Previdian sensors recorded exploitation attempts targeting this vulnerability. The cards and chart show volume, unique attackers, and daily activity.

887

Attempts observed

17

Unique attacker IPs

6

Attacker countries

BE · DE · NL · RO · SG · US

16

Sensors observed

CVE-2026-39364 exploitation attempts over the last 91 days

Daily events observed by Previdian sensors

Updated 16 Sep 2026

4
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2
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2
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0
60
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521
366
18 Jun 7 Jul 26 Jul 14 Aug 16 Sep

First observed 14 Jun 2026 · Last observed 16 Sep 2026

Pro adds sensor region and window summaries. Enterprise adds raw IPs, paths, User-Agents, and payloads.

Request telemetry access

Detection

Operational artifacts and observed signals

Make the evidence actionable in scanner, SOC, and edge-control workflows.

Observed signals

Request targets
User-Agents
Callback hosts
33
770
0

Request targets and User-Agents available in Pro. Callback host details available in Enterprise.

Virtual patch status

No Previdian virtual patch is currently available. Future rules ship for ModSecurity, Cloudflare, and AWS WAF.

Learn about virtual patches →

Attacker IP Indicators

Attacker IP indicators observed · available in Pro and Enterprise.

Sensor-derived attacker IP indicators are available to Pro and Enterprise accounts under Detection and through the Pro API.

Learn about Pro API access

Scanner Artifacts

Scanner and exploit-framework references linked to this CVE.

Scanner Reference Detected
Nuclei https://github.com/projectdiscovery/nuclei-templates/blob/main/http/cves/2026/CVE-2026-39364.yaml 01 Jun 2026

Risk and context

Severity, weaknesses, and research context

CVSS v4.0

8.2 High
CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:H/VI:N/VA:N/SC:N/SI:N/SA:N

EPSS

2.0%

Weaknesses

Incorrect Behavior Order: Validate Before Canonicalize CWE-180 Improper Access Control CWE-284 External Control of Assumed-Immutable Web Parameter CWE-472

All CVSS Scores

CVSS v4.0 8.2 High

CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:H/VI:N/VA:N/SC:N/SI:N/SA:N

CVSS v3.1 7.5 High

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N

Potential Proof of Concepts

These PoCs are unverified and could contain malware. Use at your own risk.

Vite Dev Server - Directory Traversal

nuclei · Created Unknown

https://github.com/vitejs/vite/security/advisories/GHSA-v2wj-q39q-566r

ghsa · Created Unknown · AI assessment 90%

Vite: `server.fs.deny` bypassed with queries

Timeline

From disclosure to observed exploitation

  1. 15:52 UTC

    Observed by Previdian sensors

    Evidence-backed exploitation signal

  2. 15:40 UTC

    Added to Previdian KEV Feed

    High-confidence, third-party attested exploitation

  3. 04:30 UTC

    Indicators of compromise added (24)

    Indicators of compromise recorded

  4. 14:21 UTC

    Public PoC available

    Public proof-of-concept code published

  5. 15:34 UTC

    Nuclei template available

    Scanner coverage available

  6. 19:12 UTC

    CVE published

    Vulnerability disclosed publicly

  7. 21:29 UTC

    CVE ID reserved

    Identifier reserved by the CNA

Pro API

Automate this intelligence

Confidence, exploit status, sensor telemetry, PoCs, scanner integrations, mentions, and tags are available programmatically for VM, SOC, and CTI workflows.

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  • Evidence confidence and provenance
  • First-party sensor telemetry
  • PoC and scanner references
  • Affected versions and enrichment
  • Automation-ready JSON delivery

GET /api/v2/pro/kevs/CVE-2026-39364

Free JSON includes basic KEV fields 
{
  "cve_id": "CVE-2026-39364",
  "confidence": "Confirmed",
  "cvss_score": 8.2,
  "cvss_estimated": false,
  "epss_score": 0.01996,
  "exploit_status": {
    "exploited_in_the_wild": true,
    "active_exploitation_observed": true
  },
  "sensor_telemetry": { "attempts": 887, "sensors": 16 }
}