Vulnerability report

Exploited in the wild High confidence Not in CISA KEV

CVE-2026-3965

whyour qinglong API express.ts protection mechanism

Whyour / qinglong · 2.20.0

Watch CVE-2026-3965 Browse KEV feed
Severity
CVSS 5.3 · Medium
Confidence
High
Exploit status
Exploited in the wild
EPSS
0.5%
First observed
—
Last observed
—

Decision summary

What security teams need to know first

Direct answers before the deeper technical record.

What it is

CVE-2026-3965 is whyour qinglong API express.ts protection mechanism. A security vulnerability has been detected in whyour qinglong up to 2.20.1. Affected is an unknown function of the file back/loaders/express.ts of...

Is it exploited?

Yes. Previdian tracks this CVE as a known exploited vulnerability. Confidence is high. Also confirmed by third-party sources.

Who is affected?

Whyour / qinglong 2.20.0.

What should we do?

Prioritize remediation. Validate affected assets and apply vendor fixes on an accelerated timeline.

Overview

A security vulnerability has been detected in whyour qinglong up to 2.20.1

A security vulnerability has been detected in whyour qinglong up to 2.20.1. Affected is an unknown function of the file back/loaders/express.ts of the component API Interface. The manipulation of the argument command leads to protection mechanism failure. The attack may be initiated remotely. The exploit has been disclosed publicly and may be used.

Upgrading to version 2.20.2 is able to address this issue. The identifier of the patch is 6bec52dca158481258315ba0fc2f11206df7b719. It is advisable to upgrade the affected component. The code maintainer was informed beforehand about the issues. He reacted very fast and highly professional.

whyour Affected
qinglong
2.20.0 2.20.1
whyour Unaffected
qinglong
2.20.2
View vendor advisory (opens in new tab)
Published
11 Mar 2026
Exploitation Reported
10 Apr 2026
Attack vector
Remote
Complexity
Low
Privileges
Low
User interaction
None

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

The Shadowserver

Recorded 10 Apr 2026

A trusted third party reported exploitation.

Known exploited vulnerability sources

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

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Source Added
The Shadowserver First 2026-04-10 00:00 UTC

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
0
0
0

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

Scanner coverage

No scanner integrations recorded yet.

Virtual patch status

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

Learn about virtual patches →

No detection artifacts or sensor request patterns are available for this CVE yet.

Check back as sensor telemetry and scanner integrations are updated.

Risk and context

Severity, weaknesses, and research context

CVSS v4.0

5.3 Medium

Potential damage if exploited. Separate from whether attackers are using it.

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

EPSS

0.5%

Estimated chance of exploitation in the next 30 days. Previdian's warning comes from evidence, not this score.

Weaknesses

Protection Mechanism Failure CWE-693

Recent mention · Github Advisory Database (NPM)

[@whyour/qinglong] Qinglong has an incomplete fix for CVE-2026-3965: Improper Authentication

Summary The init guard middleware in Qinglong only checks /api/user/init paths but not /open/user/init, which is whitelisted from JWT authentication and rewritten to /api/user/init after the guard has already passed, allowing unauthenticated admin credential reset on...

Read full advisory

All CVSS Scores

CVSS v4.0 5.3 Medium

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

CVSS v3.1 6.3 Medium

CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:L/A:L/E:P/RL:O/RC:C

CVSS v3.0 6.3 Medium

CVSS:3.0/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:L/A:L/E:P/RL:O/RC:C

CVSS v2.0 6.5 Medium

AV:N/AC:L/Au:S/C:P/I:P/A:P/E:POC/RL:OF/RC:C

Timeline

From disclosure to observed exploitation

  1. 00:00 UTC

    Added to Previdian KEV Feed

    High-confidence, third-party attested exploitation

  2. 23:32 UTC

    CVE published

    Vulnerability disclosed publicly

  3. 13:14 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-2026-3965

Sample API response 
{
  "cve_id": "CVE-2026-3965",
  "confidence": "High",
  "cvss_score": 5.3,
  "cvss_estimated": false,
  "epss_score": 0.00484,
  "exploit_status": {
    "exploited_in_the_wild": true,
    "active_exploitation_observed": false
  },
  "sensor_telemetry": { "attempts": 0, "sensors": 0 }
}