CVE-2021-37185

highpriority · track · 29EPSS 0.021 · 81 %ileDEEURUUS

grimoire priorityP2 · Scheduled

Exploitable?

—

no known exploitation

Likely / severe?

2.06% (81st) EPSS

CVSS 7.1 · high

Is it mine?

88 products

Check your exposure

Who says so?

5 sources

cnnvd · enisa_euvd · fstec_bdu · cisa_csaf_ot

EPSS · scored 2026-10-26

A vulnerability has been identified in SIMATIC Drive Controller family (All versions >= V2.9.2 < V2.9.4), SIMATIC ET 200SP Open Controller CPU 1515SP PC2 (incl. SIPLUS variants) (All versions >= V21.9 < V21.9.4), SIMATIC S7-1200 CPU family (incl. SIPLUS variants) (All versions >= V4.5.0 < V4.5.2), SIMATIC S7-1500 CPU family (incl. related ET200 CPUs and SIPLUS variants) (All versions >= V2.9.2 < V2.9.4), SIMATIC S7-1500 Software Controller (All versions >= V21.9 < V21.9.4), SIMATIC S7-PLCSIM Advanced (All versions >= V4.0 < V4.0 SP1), SIPLUS TIM 1531 IRC (All versions < V2.3.6), TIM 1531 IRC (All versions < V2.3.6). An unauthenticated attacker could cause a denial-of-service condition in a PLC when sending specially prepared packets over port 102/tcp. A restart of the affected device is needed to restore normal operations.

remediations

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

A vendor fix is available.

FixedSIMATIC Drive Controller familysiemens_psirt
Update to V2.9.4 or later version
https://support.industry.siemens.com/cs/ww/en/view/109773914/
FixedSIMATIC ET 200SP Open Controller CPU 1515SP PC2 (incl. SIPLUS variants)siemens_psirt
Update to V21.9.4 or later version
https://support.industry.siemens.com/cs/ww/en/view/109759122/
FixedSIMATIC S7-1200 CPU family (incl. SIPLUS variants)siemens_psirt
Update to V4.5.2 or later version
https://support.industry.siemens.com/cs/ww/en/view/109793280/
FixedSIMATIC S7-1500 CPU family (incl. related ET200 CPUs and SIPLUS variants)siemens_psirt
Update to V2.9.4 or later version
https://support.industry.siemens.com/cs/ww/en/view/109478459/
FixedSIMATIC S7-1500 Software Controllersiemens_psirt
Update to V21.9.4 or later version
https://support.industry.siemens.com/cs/ww/en/view/109478528/
FixedSIMATIC S7-PLCSIM Advancedsiemens_psirt
Update to V4.0 SP1 or later version
https://support.industry.siemens.com/cs/ww/en/view/109805271/
FixedSIPLUS TIM 1531 IRC (6AG1543-1MX00-7XE0)siemens_psirt
Update to V2.3.6 or later version
https://support.industry.siemens.com/cs/ww/en/view/109817397/
FixedTIM 1531 IRC (6GK7543-1MX00-0XE0)siemens_psirt
Update to V2.3.6 or later version
https://support.industry.siemens.com/cs/ww/en/view/109817397/
FixedSIMATIC Drive Controller familycisa_csaf_ot
Update to V2.9.4 or later version
https://support.industry.siemens.com/cs/ww/en/view/109773914/
FixedSIMATIC ET 200SP Open Controller CPU 1515SP PC2 (incl. SIPLUS variants)cisa_csaf_ot
Update to V21.9.4 or later version
https://support.industry.siemens.com/cs/ww/en/view/109759122/
FixedSIMATIC S7-1200 CPU family (incl. SIPLUS variants)cisa_csaf_ot
Update to V4.5.2 or later version
https://support.industry.siemens.com/cs/ww/en/view/109793280/
FixedSIMATIC S7-1500 CPU family (incl. related ET200 CPUs and SIPLUS variants)cisa_csaf_ot
Update to V2.9.4 or later version
https://support.industry.siemens.com/cs/ww/en/view/109478459/
FixedSIMATIC S7-1500 Software Controllercisa_csaf_ot
Update to V21.9.4 or later version
https://support.industry.siemens.com/cs/ww/en/view/109478528/
FixedSIMATIC S7-PLCSIM Advancedcisa_csaf_ot
Update to V4.0 SP1 or later version
https://support.industry.siemens.com/cs/ww/en/view/109805271/
FixedSIPLUS TIM 1531 IRC (6AG1543-1MX00-7XE0)cisa_csaf_ot
Update to V2.3.6 or later version
https://support.industry.siemens.com/cs/ww/en/view/109817397/
FixedTIM 1531 IRC (6GK7543-1MX00-0XE0)cisa_csaf_ot
Update to V2.3.6 or later version
https://support.industry.siemens.com/cs/ww/en/view/109817397/

cvss

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

7.5

010

base score 0–10 · higher = more severe · hover a vector to decode⚠ sources disagree · medium–high · 6–7.5

v2.07.1highAV:N/AC:M/Au:N/C:N/I:N/A:Cprimary · NVD / NIST USexploitability 8.6 · impact 6.9

v2.06mediumAV:N/AC:M/Au:N/C:N/I:N/A:C/E:Usecondary · CVSS-BT (t0sche)

v3.17.5highCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H/E:P/RL:O/RC:Csecondary · CISA US

v3.17.5highAV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:Hsecondary · FSTEC (BDU) RU

v3.17.5highCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H/E:P/RL:O/RC:Csecondary · ENISA EU

v3.17.5highCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:Hsecondary · productcert@siemens.com DEexploitability 3.9 · impact 3.6

v3.17.5highCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H/E:P/RL:O/RC:Csecondary · Siemens ProductCERT DE

v3.17.5highCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:Hsecondary · NVD / NIST USexploitability 3.9 · impact 3.6

ssvc

A stakeholder decision — act, attend, or track — from exploitation and impact.

Exploitation: none · Automatable: yes · Technical Impact: partialcoordinatorcisa_ssvcUS

weaknesses

The CWE weakness classes this flaw belongs to.

CWE-672USCWE-672USCWE-672USCWE-672US

affected products (88)

Products and version ranges known to be affected.

SIMATIC Drive Controller familyall versionscisa_csaf_otUS
SIMATIC ET 200SP Open Controller CPU 1515SP PC2 (incl. SIPLUS variants)all versionscisa_csaf_otUS
SIMATIC S7-1200 CPU family (incl. SIPLUS variants)all versionscisa_csaf_otUS
SIMATIC S7-1500 CPU family (incl. related ET200 CPUs and SIPLUS variants)all versionscisa_csaf_otUS
SIMATIC S7-1500 Software Controllerall versionscisa_csaf_otUS
SIMATIC S7-PLCSIM Advancedall versionscisa_csaf_otUS
SIPLUS TIM 1531 IRC (6AG1543-1MX00-7XE0)all versionscisa_csaf_otUS
TIM 1531 IRC (6GK7543-1MX00-0XE0)all versionscisa_csaf_otUS
Siemens SIMATIC Drive Controller familyV2.9.2 → V2.9.4cisa_csaf_otUS
Siemens SIMATIC ET 200SP Open Controller CPU 1515SP PC2 (incl. SIPLUS variants)V21.9 → V21.9.4cisa_csaf_otUS
Siemens SIMATIC S7-1200 CPU family (incl. SIPLUS variants)V4.5.0 → V4.5.2cisa_csaf_otUS
Siemens SIMATIC S7-1500 CPU family (incl. related ET200 CPUs and SIPLUS variants)V2.9.2 → V2.9.4cisa_csaf_otUS
Siemens SIMATIC S7-1500 Software ControllerV21.9 → V21.9.4cisa_csaf_otUS
Siemens SIMATIC S7-PLCSIM AdvancedV4.0| → V4.0_SP1cisa_csaf_otUS
Siemens SIPLUS TIM 1531 IRC (6AG1543-1MX00-7XE0)< V2.3.6cisa_csaf_otUS
Siemens TIM 1531 IRC (6GK7543-1MX00-0XE0)< V2.3.6cisa_csaf_otUS
Siemens SIMATIC Drive Controller familyAll versions V2.9.2 → V2.9.4enisa_euvdEU
Siemens SIMATIC ET 200SP Open Controller CPU 1515SP PC2 (incl. SIPLUS variants)All versions V21.9 → V21.9.4enisa_euvdEU
Siemens SIMATIC S7-1200 CPU family (incl. SIPLUS variants)All versions V4.5.0 → V4.5.2enisa_euvdEU
Siemens SIMATIC S7-1500 CPU family (incl. related ET200 CPUs and SIPLUS variants)All versions V2.9.2 → V2.9.4enisa_euvdEU

showing 20 of 88

advisories (2)

Vendor and ecosystem advisories describing this.

SSA-838121SSA-838121: Multiple Denial of Service Vulnerabilities in Industrial Products2022-02-08csaf · siemens_psirtDE
Affected SIMATIC firmware contains three vulnerabilities that could allow an unauthenticated attacker to perform a denial of service attack under certain conditions. Siemens has released updates for several affected products and recommends to update to the latest versions. Siemens recommends countermeasures for products where updates are not, or not yet available.
ICSA-22-041-01Siemens SIMATIC Industrial Products (Update A)2022-02-08icsa · cisa_csaf_otUS
Affected SIMATIC firmware contains three vulnerabilities that could allow an unauthenticated attacker to perform a denial of service attack under certain conditions. Siemens has released updates for several affected products and recommends to update to the latest versions. Siemens recommends countermeasures for products where updates are not, or not yet available.

also known as (4)

Other names and identifiers for this entity.

sources

Which sources assert this record, and when.

cnnvd enisa_euvd fstec_bdu cisa_csaf_ot siemens_psirt NVD CVE.org MITRE

published 2022-02-09modified 2026-06-17

references (8)

External citations — patches, advisories, analysis.

scry

Attackers weaponise vulnerabilities like this against internet-exposed services. See what is exposed on your perimeter with a free passive scan.

Free scan