Vulnerability report

Exploited in the wild High confidence Not in CISA KEV

CVE-2021-4462

Employee Records System v1.0 Arbitrary File Upload RCE

Employee Records System · 1.0

Watch CVE-2021-4462 Browse KEV feed
Severity
CVSS 9.3 · Critical
Confidence
High
Exploit status
Exploited in the wild
EPSS
3.4%
First observed
—
Last observed
—

Decision summary

What security teams need to know first

Direct answers before the deeper technical record.

What it is

CVE-2021-4462 is an unauthenticated Employee Records System v1.0 Arbitrary File Upload RCE.

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?

Employee Records System 1.0.

What should we do?

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

Overview

Employee Records System v1.0 Arbitrary File Upload RCE

Employee Records System version 1.0 contains an unrestricted file upload vulnerability that allows a remote unauthenticated attacker to upload arbitrary files via the uploadID.php endpoint; uploaded files can be executed because the application does not perform proper server-side validation. Exploitation evidence was observed by the Shadowserver Foundation on 2025-02-06 UTC.

Employee Records System Affected
Employee Records System
1.0
View vendor advisory (opens in new tab)
Published
10 Nov 2025
Exploitation Reported
26 Feb 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

The Shadowserver

Recorded 26 Feb 2026

A trusted third party reported exploitation.

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
The Shadowserver First 2026-02-26 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.

Virtual patch status

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

Learn about virtual patches →

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/2021/CVE-2021-4462.yaml 01 Jun 2026

Risk and context

Severity, weaknesses, and research context

CVSS v4.0

9.3 Critical

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

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

EPSS

3.4%

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

Weaknesses

Unrestricted Upload of File with Dangerous Type CWE-434

Potential Proof of Concepts

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

Employee Records System 1.0 - Unauthenticated File Upload RCE

nuclei · Created Unknown

Timeline

From disclosure to observed exploitation

  1. 14:20 UTC

    Public PoC available

    Public proof-of-concept code published

  2. 15:34 UTC

    Nuclei template available

    Scanner coverage available

  3. 00:00 UTC

    Added to Previdian KEV Feed

    High-confidence, third-party attested exploitation

  4. 22:32 UTC

    CVE published

    Vulnerability disclosed publicly

  5. 20:14 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-2021-4462

Sample API response 
{
  "cve_id": "CVE-2021-4462",
  "confidence": "High",
  "cvss_score": 9.3,
  "cvss_estimated": false,
  "epss_score": 0.03417,
  "exploit_status": {
    "exploited_in_the_wild": true,
    "active_exploitation_observed": false
  },
  "sensor_telemetry": { "attempts": 0, "sensors": 0 }
}