Is CVE-2020-35665 actively exploited?

Yes. KEV Intelligence tracks CVE-2020-35665 as a known exploited vulnerability. Confidence is high.

What exploitation activity has KEV Intelligence observed?

KEV Intelligence has not yet recorded sensor-observed exploitation attempts for CVE-2020-35665. Our sensors continue to monitor for activity targeting this CVE.

Which versions are affected?

Version-level data is not available; KEV Intelligence tracks TerraMaster TOS.

No. CVE-2020-35665 is not currently listed in CISA KEV.

Vulnerability report

Exploited in the wild High confidence Not in CISA KEV

CVE-2020-35665

TOS

TerraMaster / TOS

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Severity: CVSS 9.8 · Critical
Confidence: High
Exploit status: Exploited in the wild
EPSS: 78.5%
First observed: —
Last observed: —

Decision summary

What security teams need to know first

Direct answers before the deeper technical record.

What it is

CVE-2020-35665 is an unauthenticated vulnerability affecting TerraMaster TOS. An unauthenticated command-execution vulnerability exists in TerraMaster TOS through 4.2.06 via shell metacharacters in the Event parameter...

Is it exploited?

Yes. KEV Intelligence tracks this CVE as a known exploited vulnerability. Confidence is high.

Who is affected?

TerraMaster / TOS.

What should we do?

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

Overview

TOS

An unauthenticated command-execution vulnerability exists in TerraMaster TOS through 4.2.06 via shell metacharacters in the Event parameter in include/makecvs.php during CSV creation.

Published: 23 Dec 2020
Exploitation Reported: 27 Apr 2025
Attack vector: Remote
Complexity: Low
Privileges: None
User interaction: None

CVE References

CVE Record CVE.org · CVE Record https://www.cve.org/CVERecord?id=CVE-2020-35665
49330 exploit-db.com · Exploit https://www.exploit-db.com/exploits/49330
pentest.com.tr/exploits/TerraMaster-TOS-4-2-06-Unauthentica... pentest.com.tr · CVE Record https://www.pentest.com.tr/exploits/TerraMaster-TOS-4-2-06-Unauthenti...
packetstormsecurity.com/files/172880/TerraMaster-TOS-4.2.06-Remote-C... packetstormsecurity.com · CVE Record http://packetstormsecurity.com/files/172880/TerraMaster-TOS-4.2.06-Re...

Exploitation evidence

Why KEV Intelligence 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 27 Apr 2025

Independent exploitation attestation added to the KEV Intelligence record.

Known exploited vulnerability sources

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

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Source	Added
The Shadowserver First	2025-04-27 00:00 UTC

Detection

Operational artifacts and observed signals

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

Observed signals

Request targets: 0
User-Agents: 0

Raw values available in Pro and Enterprise.

Scanner coverage

Metasploit template detected 28 Apr 2025.

View Metasploit template

Virtual patch status

No KEV Intelligence 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
Metasploit	https://github.com/rapid7/metasploit-framework/blob/master/modules/exploits/linux/http/terramaster_unauth_rce_cve_2020_35665.rb	28 Apr 2025

Risk and context

Severity, weaknesses, and research context

CVSS v3.1

9.8 Critical

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

EPSS

78.5%

Weaknesses

Improper Neutralization of Special Elements used in an OS Command ('OS Command Injection') CWE-78

All CVSS Scores

CVSS v3.1 9.8 Critical

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

CVSS v2.0 10.0 High

AV:N/AC:L/Au:N/C:C/I:C/A:C

Timeline

From disclosure to observed exploitation

28 Apr 2025
Metasploit module available

Exploit module available
27 Apr 2025
Added to KEV Intelligence KEV Feed

High-confidence, third-party attested exploitation
23 Dec 2020
CVE published

Vulnerability disclosed publicly
23 Dec 2020
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-2020-35665

Free JSON includes basic KEV fields

{
  "cve_id": "CVE-2020-35665",
  "confidence": "High",
  "cvss_score": 9.8,
  "cvss_estimated": false,
  "epss_score": 0.7848,
  "exploit_status": {
    "exploited_in_the_wild": true,
    "active_exploitation_observed": false
  },
  "sensor_telemetry": { "attempts": 0, "sensors": 0 }
}

Early warning alerts

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