CVE-2021-33841Network attack vector

Unauthenticated code execution via mishandled requests

Published Jun 9, 2021 · Updated Sep 16, 2024

OS command injection in CIRCUTOR SGE-PLC1000 firmware 0.9.2b allows remote attackers to execute code with maximum OS privileges. The affected request, parameter, and handler are undisclosed; INCIBE states only that the device mishandles some requests before injecting code into the operating system. No authentication or user interaction is required, and successful exploitation grants maximum privileges over the embedded operating system.

CVSS severity10.0
Critical
EPSS probability2.25%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

OS command injection in CIRCUTOR SGE-PLC1000 firmware 0.9.2b allows remote attackers to execute code with maximum OS privileges. The affected request, parameter, and handler are undisclosed; INCIBE states only that the device mishandles some requests before injecting code into the operating system. No authentication or user interaction is required, and successful exploitation grants maximum privileges over the embedded operating system.

The record

CVE
CVE-2021-33841
Published
Jun 9, 2021
Updated
Sep 16, 2024
Vendor
CIRCUTOR
Product
SGE-PLC1000
Classifications
CWE-78, T1059
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Jun 9, 2021CVE publishedPublication date reported by the CVE source.
  2. Sep 16, 2024Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

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Is a vulnerable build present?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=0.9.2b

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

CIRCUTOR · SGE-PLC1000version=0.9.2b

Published CVSS scores

10.0INCIBECVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:H
9.8NIST NVDCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
10.0NIST NVDAV:N/AC:L/Au:N/C:C/I:C/A:C

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

Daily unique IPsNo honeypot observations are available for this CVE in the selected window.

No observations available

Sep 10, 2026Sep 16, 2026
Latest reporting daySep 16, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-78Improper Neutralization of Special Elements used in an OS Command ('OS Command Injection')
T1059Command and Scripting Interpreter

Public exploit references

No public exploit references are available in this record.

Labels summarize the accepted research assessment. They do not indicate a test against your environment.

Technologies

Your stack

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Your stack

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