CVE-2021-25667

mediumpriority · track · 35EPSS 0.010 · 61 %ileDEEURUUS

grimoire priorityP3 · Track

Exploitable?

—

no known exploitation

Likely / severe?

0.95% (61st) EPSS

CVSS 5.8 · medium

Is it mine?

84 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 RUGGEDCOM RM1224 (All versions >= V4.3 and < V6.4), SCALANCE M-800 (All versions >= V4.3 and < V6.4), SCALANCE S615 (All versions >= V4.3 and < V6.4), SCALANCE SC-600 Family (All versions >= V2.0 and < V2.1.3), SCALANCE XB-200 (All versions < V4.1), SCALANCE XC-200 (All versions < V4.1), SCALANCE XF-200BA (All versions < V4.1), SCALANCE XM400 (All versions < V6.2), SCALANCE XP-200 (All versions < V4.1), SCALANCE XR-300WG (All versions < V4.1), SCALANCE XR500 (All versions < V6.2). Affected devices contain a stack-based buffer overflow vulnerability in the handling of STP BPDU frames that could allow a remote attacker to trigger a denial-of-service condition or potentially remote code execution. Successful exploitation requires the passive listening feature of the device to be active.

remediations

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

A vendor fix is available.

FixedRUGGEDCOM RM1224siemens_psirt
Update to V6.4 or later version
https://support.industry.siemens.com/cs/ww/en/view/109794349/
FixedSCALANCE M-800siemens_psirt
Update to V6.4 or later version
https://support.industry.siemens.com/cs/ww/en/view/109794349/
FixedSCALANCE S615siemens_psirt
Update to V6.4 or later version
https://support.industry.siemens.com/cs/ww/en/view/109794349/
FixedSCALANCE SC-600 Familysiemens_psirt
Update to V2.1.3 or later version
https://support.industry.siemens.com/cs/ww/en/view/109793041/
FixedSCALANCE XB-200siemens_psirt
Update to V4.1 or later version
https://support.industry.siemens.com/cs/ww/en/view/109762982/
FixedSCALANCE XC-200siemens_psirt
Update to V4.1 or later version
https://support.industry.siemens.com/cs/ww/en/view/109762982/
FixedSCALANCE XF-200BAsiemens_psirt
Update to V4.1 or later version
https://support.industry.siemens.com/cs/ww/en/view/109762982/
FixedSCALANCE XM400siemens_psirt
Update to V6.2 or later version
https://support.industry.siemens.com/cs/ww/en/view/109764409/
FixedSCALANCE XP-200siemens_psirt
Update to V4.1 or later version
https://support.industry.siemens.com/cs/ww/en/view/109762982/
FixedSCALANCE XR-300WGsiemens_psirt
Update to V4.1 or later version
https://support.industry.siemens.com/cs/ww/en/view/109762982/
FixedSCALANCE XR500siemens_psirt
Update to V6.2 or later version
https://support.industry.siemens.com/cs/ww/en/view/109761425/
FixedRUGGEDCOM RM1224cisa_csaf_ot
Update to V6.4 or later version
https://support.industry.siemens.com/cs/ww/en/view/109794349/
FixedSCALANCE M-800cisa_csaf_ot
Update to V6.4 or later version
https://support.industry.siemens.com/cs/ww/en/view/109794349/
FixedSCALANCE S615cisa_csaf_ot
Update to V6.4 or later version
https://support.industry.siemens.com/cs/ww/en/view/109794349/
FixedSCALANCE SC-600 Familycisa_csaf_ot
Update to V2.1.3 or later version
https://support.industry.siemens.com/cs/ww/en/view/109793041/
FixedSCALANCE XB-200cisa_csaf_ot
Update to V4.1 or later version
https://support.industry.siemens.com/cs/ww/en/view/109762982/
FixedSCALANCE XC-200cisa_csaf_ot
Update to V4.1 or later version
https://support.industry.siemens.com/cs/ww/en/view/109762982/
FixedSCALANCE XF-200BAcisa_csaf_ot
Update to V4.1 or later version
https://support.industry.siemens.com/cs/ww/en/view/109762982/
FixedSCALANCE XM400cisa_csaf_ot
Update to V6.2 or later version
https://support.industry.siemens.com/cs/ww/en/view/109764409/
FixedSCALANCE XP-200cisa_csaf_ot
Update to V4.1 or later version
https://support.industry.siemens.com/cs/ww/en/view/109762982/
FixedSCALANCE XR-300WGcisa_csaf_ot
Update to V4.1 or later version
https://support.industry.siemens.com/cs/ww/en/view/109762982/
FixedSCALANCE XR500cisa_csaf_ot
Update to V6.2 or later version
https://support.industry.siemens.com/cs/ww/en/view/109761425/
MitigationRUGGEDCOM RM1224siemens_psirt
Deactivate the STP passive listening feature of the vulnerable devices
MitigationSCALANCE M-800siemens_psirt
Deactivate the STP passive listening feature of the vulnerable devices
MitigationSCALANCE S615siemens_psirt
Deactivate the STP passive listening feature of the vulnerable devices
MitigationSCALANCE SC-600 Familysiemens_psirt
Deactivate the STP passive listening feature of the vulnerable devices
MitigationSCALANCE XB-200siemens_psirt
Deactivate the STP passive listening feature of the vulnerable devices
MitigationSCALANCE XC-200siemens_psirt
Deactivate the STP passive listening feature of the vulnerable devices
MitigationSCALANCE XF-200BAsiemens_psirt
Deactivate the STP passive listening feature of the vulnerable devices
MitigationSCALANCE XM400siemens_psirt
Deactivate the STP passive listening feature of the vulnerable devices
MitigationSCALANCE XP-200siemens_psirt
Deactivate the STP passive listening feature of the vulnerable devices
MitigationSCALANCE XR-300WGsiemens_psirt
Deactivate the STP passive listening feature of the vulnerable devices
MitigationSCALANCE XR500siemens_psirt
Deactivate the STP passive listening feature of the vulnerable devices
MitigationRUGGEDCOM RM1224cisa_csaf_ot
Deactivate the STP passive listening feature of the vulnerable devices
MitigationSCALANCE M-800cisa_csaf_ot
Deactivate the STP passive listening feature of the vulnerable devices
MitigationSCALANCE S615cisa_csaf_ot
Deactivate the STP passive listening feature of the vulnerable devices
MitigationSCALANCE SC-600 Familycisa_csaf_ot
Deactivate the STP passive listening feature of the vulnerable devices
MitigationSCALANCE XB-200cisa_csaf_ot
Deactivate the STP passive listening feature of the vulnerable devices
MitigationSCALANCE XC-200cisa_csaf_ot
Deactivate the STP passive listening feature of the vulnerable devices
MitigationSCALANCE XF-200BAcisa_csaf_ot
Deactivate the STP passive listening feature of the vulnerable devices
MitigationSCALANCE XM400cisa_csaf_ot
Deactivate the STP passive listening feature of the vulnerable devices
MitigationSCALANCE XP-200cisa_csaf_ot
Deactivate the STP passive listening feature of the vulnerable devices
MitigationSCALANCE XR-300WGcisa_csaf_ot
Deactivate the STP passive listening feature of the vulnerable devices
MitigationSCALANCE XR500cisa_csaf_ot
Deactivate the STP passive listening feature of the vulnerable devices

cvss

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

8.8

010

base score 0–10 · higher = more severe · hover a vector to decode⚠ sources disagree · medium–high · 5.8–8.8

v2.05.8mediumAV:A/AC:L/Au:N/C:P/I:P/A:Pprimary · NVD / NIST USexploitability 6.5 · impact 6.4

v3.18.8highCVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:Hprimary · NVD / NIST USexploitability 2.8 · impact 5.9

v3.18.8highCVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H/E:P/RL:O/RC:Csecondary · CISA US

v3.18.8highAV:A/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:Hsecondary · FSTEC (BDU) RU

v3.16.5mediumCVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:Hsecondary · ENISA EU

v3.16.5mediumCVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:Hsecondaryexploitability 2.8 · impact 3.6

v3.18.8highCVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H/E:P/RL:O/RC:Csecondary · Siemens ProductCERT DE

v3.18.1highCVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H/E:Usecondary · CVSS-BT (t0sche)

ssvc

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

Exploitation: none · Automatable: no · Technical Impact: totalcoordinatorcisa_ssvcUS

weaknesses

The CWE weakness classes this flaw belongs to.

CWE-121USCWE-121USCWE-121USCWE-121USCWE-787USCWE-787US

affected products (84)

Products and version ranges known to be affected.

RUGGEDCOM RM1224all versionscisa_csaf_otUS
SCALANCE M-800all versionscisa_csaf_otUS
SCALANCE S615all versionscisa_csaf_otUS
SCALANCE SC-600 familyall versionscisa_csaf_otUS
SCALANCE XB-200all versionscisa_csaf_otUS
SCALANCE XC-200all versionscisa_csaf_otUS
SCALANCE XF-200BAall versionscisa_csaf_otUS
SCALANCE XM400all versionscisa_csaf_otUS
SCALANCE XP-200all versionscisa_csaf_otUS
SCALANCE XR-300WGall versionscisa_csaf_otUS
SCALANCE XR500all versionscisa_csaf_otUS
Siemens RUGGEDCOM RM1224V4.3_and_ → V6.4cisa_csaf_otUS
Siemens SCALANCE M-800V4.3_and_ → V6.4cisa_csaf_otUS
Siemens SCALANCE S615V4.3_and_ → V6.4cisa_csaf_otUS
Siemens SCALANCE SC-600 FamilyV2.0_and_ → V2.1.3cisa_csaf_otUS
Siemens SCALANCE XB-200< V4.1cisa_csaf_otUS
Siemens SCALANCE XC-200< V4.1cisa_csaf_otUS
Siemens SCALANCE XF-200BA< V4.1cisa_csaf_otUS
Siemens SCALANCE XM400< V6.2cisa_csaf_otUS
Siemens SCALANCE XP-200< V4.1cisa_csaf_otUS

showing 20 of 84

advisories (2)

Vendor and ecosystem advisories describing this.

SSA-979775SSA-979775: Stack Overflow Vulnerability in SCALANCE and RUGGEDCOM Devices2021-03-09csaf · siemens_psirtDE
Several firmware versions of the SCALANCE and RUGGEDCOM devices listed below are affected by a vulnerability in the passive listening feature that could allow an attacker to cause a reboot or, under specific circumstances, attain remote code execution of the affected devices. Siemens has released updates for the affected products and recommends to update to the latest versions.
ICSA-21-068-03Siemens SCALANCE and RUGGEDCOM Devices (Update A)2021-03-09icsa · cisa_csaf_otUS
Several firmware versions of the SCALANCE and RUGGEDCOM devices listed below are affected by a vulnerability in the passive listening feature that could allow an attacker to cause a reboot or, under specific circumstances, attain remote code execution of the affected devices. Siemens has released updates for the affected products and recommends to update to the latest versions.

also known as (6)

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 2021-03-15modified 2026-06-17

references (9)

External citations — patches, advisories, analysis.

scry

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