CVE-2021-33721Network attack vector

System code execution via malformed batch operations

Published Aug 10, 2021 · Updated Aug 3, 2024

OS command injection in Siemens SINEC NMS before 1.0 SP2 allows remote authenticated users with administrative privileges to execute code. The batch-operation creation path fails to neutralize shell metacharacters in attacker-controlled elements before forming an operating-system command. Exploitation requires an administrative application account and yields arbitrary code execution with system privileges, allowing complete control of the host.

CVSS severity7.2
High
EPSS probability2.67%
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 Siemens SINEC NMS before 1.0 SP2 allows remote authenticated users with administrative privileges to execute code. The batch-operation creation path fails to neutralize shell metacharacters in attacker-controlled elements before forming an operating-system command. Exploitation requires an administrative application account and yields arbitrary code execution with system privileges, allowing complete control of the host.

The record

CVE
CVE-2021-33721
Published
Aug 10, 2021
Updated
Aug 3, 2024
Vendor
Siemens
Product
SINEC NMS
Classifications
CWE-78, T1059
Attack vector
network
Privileges
admin

Timeline

How it unfolded

  1. Aug 10, 2021CVE publishedPublication date reported by the CVE source.
  2. Aug 3, 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=All versions < V1.0 SP2

What conditions does exploitation require?

Attack vectornetwork
Required privilegesadmin

What is affected?

Siemens · SINEC NMSversion=All versions < V1.0 SP2

Published CVSS scores

7.2NIST NVDCVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:H
9.0NIST NVDAV:N/AC:L/Au:S/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
Privilegesadmin
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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