Webserver detection of TerraMaster TOS CVE-2020-28188 exploit requests

Flags GET requests to /include/makecvs.php with Event plus indicators of script download/execute behavior tied to CVE-2020-28188.

FreeReviewedSigma · High · v5

Category: webserver
Author: Bhabesh Raj (SigmaHQ), DRL 1.1
Published: 2021-01-25
Updated: 2026-07-31

Analysis Detection

ATT&CK techniques

Initial Access

Recon
Resource Dev
Initial Access
- T1190Exploit Public-Facing Application
Execution
Persistence
Priv Esc
Defense Evasion
Cred Access
Discovery
Lateral Movement
Collection
C2
Exfiltration
Impact

What it detects

This rule identifies HTTP GET requests targeting /include/makecvs.php with query parameters indicative of TerraMaster TOS exploitation. It further requires payload elements commonly seen in post-exploitation command activity, such as curl/wget usage, script downloads (.py/.sh), permission changes (chmod), and related placeholders. The detection relies on webserver request telemetry capturing the full URI and query string.

Reporting behind it

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Webserver detection of TerraMaster TOS CVE-2020-28188 exploit requests

Pivot detection · T1190 · 9 related

Changelog

v5
Candidate ingested via manual entry.2026-07-31
v4
Candidate ingested via manual entry.2026-07-31
v3
Candidate ingested via manual entry.2026-07-31
v2
Candidate ingested via manual entry.2026-07-31
v1
No changelog recorded for this version.2026-07-30

Detection content is published as a reviewed draft. Tune thresholds and exclusions against your own telemetry before enabling this rule for alerting.

terramaster-tos-cve-2020-28188-web-exploit-attempt-via-suspicious-makecvs-php-ge-15c312b9

title: Webserver detection of TerraMaster TOS CVE-2020-28188 exploit requests
id: ffb5ad72-2239-408a-bbd9-1fc4390a3e67
status: test
description: This rule identifies HTTP GET requests targeting /include/makecvs.php with query parameters indicative of TerraMaster TOS exploitation. It further requires payload elements commonly seen in post-exploitation command activity, such as curl/wget usage, script downloads (.py/.sh), permission changes (chmod), and related placeholders. The detection relies on webserver request telemetry capturing the full URI and query string.
references:
  - https://www.ihteam.net/advisory/terramaster-tos-multiple-vulnerabilities/
  - https://research.checkpoint.com/2021/freakout-leveraging-newest-vulnerabilities-for-creating-a-botnet/
  - https://github.com/SigmaHQ/sigma/blob/master/rules-emerging-threats/2020/Exploits/CVE-2020-28188/web_cve_2020_28188_terramaster_rce_exploit.yml
author: Bhabesh Raj, Huntrule Team
date: 2021-01-25
modified: 2023-01-02
tags:
  - attack.t1190
  - attack.initial-access
  - cve.2020-28188
  - detection.emerging-threats
logsource:
  category: webserver
detection:
  base_url:
    cs-method: GET
    cs-uri-query|contains|all:
      - /include/makecvs.php
      - ?Event=
  payload:
    cs-uri-query|contains:
      - curl
      - wget
      - .py
      - .sh
      - chmod
      - _GET
  condition: base_url and payload
falsepositives:
  - Unknown
level: high
license: DRL-1.1
related:
  - id: 15c312b9-00d0-4feb-8870-7d940a4bdc5e
    type: derived

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