CVE-2023-36521

highpriority · track · 30EPSS 0.006 · 50 %ileDEEURUUS

grimoire priorityP2 · Scheduled

Exploitable?

—

no known exploitation

Likely / severe?

0.63% (50th) EPSS

CVSS 7.5 · high

Is it mine?

36 products

Check your exposure

Who says so?

5 sources

cnnvd · enisa_euvd · fstec_bdu · cisa_csaf_ot

EPSS · scored 2026-10-27

A vulnerability has been identified in SIMATIC MV540 H (All versions < V3.3.4), SIMATIC MV540 S (All versions < V3.3.4), SIMATIC MV550 H (All versions < V3.3.4), SIMATIC MV550 S (All versions < V3.3.4), SIMATIC MV560 U (All versions < V3.3.4), SIMATIC MV560 X (All versions < V3.3.4). The result synchronization server of the affected products contains a vulnerability that may lead to a denial of service condition. An attacker may cause a denial of service situation of all socket-based communication of the affected products if the result server is enabled.

remediations

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

A vendor fix is available.

FixedSIMATIC MV540 H (6GF3540-0GE10)siemens_psirt
Update to V3.3.4 or later version
https://support.industry.siemens.com/cs/ww/en/view/109821128/
FixedSIMATIC MV540 S (6GF3540-0CD10)siemens_psirt
Update to V3.3.4 or later version
https://support.industry.siemens.com/cs/ww/en/view/109821128/
FixedSIMATIC MV550 H (6GF3550-0GE10)siemens_psirt
Update to V3.3.4 or later version
https://support.industry.siemens.com/cs/ww/en/view/109821128/
FixedSIMATIC MV550 S (6GF3550-0CD10)siemens_psirt
Update to V3.3.4 or later version
https://support.industry.siemens.com/cs/ww/en/view/109821128/
FixedSIMATIC MV560 U (6GF3560-0LE10)siemens_psirt
Update to V3.3.4 or later version
https://support.industry.siemens.com/cs/ww/en/view/109821128/
FixedSIMATIC MV560 X (6GF3560-0HE10)siemens_psirt
Update to V3.3.4 or later version
https://support.industry.siemens.com/cs/ww/en/view/109821128/
FixedSIMATIC MV540 H (6GF3540-0GE10)cisa_csaf_ot
Update to V3.3.4 or later version
https://support.industry.siemens.com/cs/ww/en/view/109821128/
FixedSIMATIC MV540 S (6GF3540-0CD10)cisa_csaf_ot
Update to V3.3.4 or later version
https://support.industry.siemens.com/cs/ww/en/view/109821128/
FixedSIMATIC MV550 H (6GF3550-0GE10)cisa_csaf_ot
Update to V3.3.4 or later version
https://support.industry.siemens.com/cs/ww/en/view/109821128/
FixedSIMATIC MV550 S (6GF3550-0CD10)cisa_csaf_ot
Update to V3.3.4 or later version
https://support.industry.siemens.com/cs/ww/en/view/109821128/
FixedSIMATIC MV560 U (6GF3560-0LE10)cisa_csaf_ot
Update to V3.3.4 or later version
https://support.industry.siemens.com/cs/ww/en/view/109821128/
FixedSIMATIC MV560 X (6GF3560-0HE10)cisa_csaf_ot
Update to V3.3.4 or later version
https://support.industry.siemens.com/cs/ww/en/view/109821128/

cvss

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

8.6

010

base score 0–10 · higher = more severe · hover a vector to decode⚠ sources disagree · medium–high · 6.9–8.6

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

v3.18.6highCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:H/E:P/RL:O/RC:Csecondary · CISA US

v3.18.6highAV:N/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:Hsecondary · FSTEC (BDU) RU

v3.18.6highCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:H/E:P/RL:O/RC:Csecondary · ENISA EU

v3.18.6highCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:Hsecondary · productcert@siemens.com DEexploitability 3.9 · impact 4

v3.18.6highCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:H/E:P/RL:O/RC:Csecondary · Siemens ProductCERT DE

v3.16.9mediumCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H/E:Usecondary · CVSS-BT (t0sche)

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-770USprimaryCWE-770USCWE-770USCWE-770US

affected products (36)

Products and version ranges known to be affected.

SIMATIC MV540 H (6GF3540-0GE10)all versionscisa_csaf_otUS
SIMATIC MV540 S (6GF3540-0CD10)all versionscisa_csaf_otUS
SIMATIC MV550 H (6GF3550-0GE10)all versionscisa_csaf_otUS
SIMATIC MV550 S (6GF3550-0CD10)all versionscisa_csaf_otUS
SIMATIC MV560 U (6GF3560-0LE10)all versionscisa_csaf_otUS
SIMATIC MV560 X (6GF3560-0HE10)all versionscisa_csaf_otUS
Siemens SIMATIC MV540 H (6GF3540-0GE10)< V3.3.4cisa_csaf_otUS
Siemens SIMATIC MV540 S (6GF3540-0CD10)< V3.3.4cisa_csaf_otUS
Siemens SIMATIC MV550 H (6GF3550-0GE10)< V3.3.4cisa_csaf_otUS
Siemens SIMATIC MV550 S (6GF3550-0CD10)< V3.3.4cisa_csaf_otUS
Siemens SIMATIC MV560 U (6GF3560-0LE10)< V3.3.4cisa_csaf_otUS
Siemens SIMATIC MV560 X (6GF3560-0HE10)< V3.3.4cisa_csaf_otUS
Siemens SIMATIC MV540 HAll versions → V3.3.4enisa_euvdEU
Siemens SIMATIC MV540 SAll versions → V3.3.4enisa_euvdEU
Siemens SIMATIC MV550 HAll versions → V3.3.4enisa_euvdEU
Siemens SIMATIC MV550 SAll versions → V3.3.4enisa_euvdEU
Siemens SIMATIC MV560 UAll versions → V3.3.4enisa_euvdEU
Siemens SIMATIC MV560 XAll versions → V3.3.4enisa_euvdEU
Siemens AG SIMATIC MV540 H≤ 3.3.4fstec_bduRU
Siemens AG SIMATIC MV540 S≤ 3.3.4fstec_bduRU

showing 20 of 36

advisories (2)

Vendor and ecosystem advisories describing this.

SSA-561322SSA-561322: Multiple Vulnerabilities in SIMATIC MV500 Devices before V3.3.42023-07-11csaf · siemens_psirtDE
SIMATIC MV500 devices before V3.3.4 are affected by multiple vulnerabilities in the web server and several third-party components. Siemens has released updates for the affected products and recommends to update to the latest versions.
ICSA-23-194-04Siemens SIMATIC MV500 Devices2023-07-11icsa · cisa_csaf_otUS
SIMATIC MV500 devices before V3.3.4 are affected by multiple vulnerabilities in the web server and several third-party components. Siemens has released updates for the affected products and recommends to update to the latest versions.

also known as (5)

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 2023-07-11modified 2026-10-23

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+3263 more

references (4)

External citations — patches, advisories, analysis.

scry

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