CVE-2021-33721

highpriority · track · 30EPSS 0.027 · 86 %ileDEEUUS

grimoire priorityP2 · Scheduled

Exploitable?

—

no known exploitation

Likely / severe?

2.67% (86th) EPSS

CVSS 9 · high

Is it mine?

6 products

Check your exposure

Who says so?

5 sources

cnnvd · enisa_euvd · cisa_csaf_ot · nvd

EPSS · scored 2026-10-27

A vulnerability has been identified in SINEC NMS (All versions < V1.0 SP2). The affected application incorrectly neutralizes special elements when creating batch operations which could lead to command injection. An authenticated remote attacker with administrative privileges could exploit this vulnerability to execute arbitrary code on the system with system privileges.

remediations

Vendor fix, mitigation, or workaround guidance, as published by each source.

A vendor fix is available.

FixedSINEC NMSsiemens_psirt
Update to V1.0 SP2 or later version
https://support.industry.siemens.com/cs/ww/en/view/109797645/
FixedSINEC NMScisa_csaf_ot
Update to V1.0 SP2 or later version
https://support.industry.siemens.com/cs/ww/en/view/109797645/

cvss

Technical severity, 0–10. One row per scoring source.

9.0

010

base score 0–10 · higher = more severe · hover a vector to decode⚠ sources disagree · medium–high · 6.6–9

v2.09highAV:N/AC:L/Au:S/C:C/I:C/A:Cprimary · NVD / NIST USexploitability 8 · impact 10

v3.17.2highCVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:Hprimary · NVD / NIST USexploitability 1.2 · impact 5.9

v3.17.2highCVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:H/E:P/RL:O/RC:Csecondary · CISA US

v3.17.2highCVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:H/E:P/RL:O/RC:Csecondary · Siemens ProductCERT DE

v3.16.6mediumCVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:H/E:Usecondary · CVSS-BT (t0sche)

weaknesses

The CWE weakness classes this flaw belongs to.

CWE-78USprimaryCWE-78USCWE-78US

affected products (6)

Products and version ranges known to be affected.

SINEC NMSall versionscisa_csaf_otUS
Siemens SINEC NMS< V1.0_SP2cisa_csaf_otUS
Siemens SINEC NMSAll versions → V1.0 SP2enisa_euvdEU
siemens sinec network management system< 1.0nvdUScpe:2.3:a:siemens:sinec_network_management_system:*:*:*:*:*:*:*:*
siemens sinec network management system= 1.0nvdUScpe:2.3:a:siemens:sinec_network_management_system:*:*:*:*:*:*:*:*
Siemens SINEC NMS< V1.0 SP2siemens_psirtDE

advisories (2)

Vendor and ecosystem advisories describing this.

SSA-756744SSA-756744: OS Command Injection Vulnerability in SINEC NMS2021-08-10csaf · siemens_psirtDE
The latest update for SINEC NMS fixes a vulnerability that could allow an authenticated remote attacker to execute arbitrary code on the system, with system privileges, under certain conditions. Siemens has released an update for SINEC NMS and recommends to update to the latest version.
ICSA-21-222-04Siemens SINEC NMS2021-08-10icsa · cisa_csaf_otUS
The latest update for SINEC NMS fixes a vulnerability that could allow an authenticated remote attacker to execute arbitrary code on the system, with system privileges, under certain conditions. Siemens has released an update for SINEC NMS and recommends to update to the latest version.

also known as (3)

Other names and identifiers for this entity.

sources

Which sources assert this record, and when.

cnnvd enisa_euvd cisa_csaf_ot nvd siemens_psirt NVD CVE.org MITRE

published 2021-08-10modified 2026-06-17

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references (6)

External citations — patches, advisories, analysis.

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