CVE-2021-25667

Name: CVE-2021-25667
Creator: NVD / NIST
Published: 2021-03-15T17:15:21.69+00:00
License: https://creativecommons.org/publicdomain/zero/1.0/

HIGHCVSS 8.8/10EPSS 0.85%

Last modified Jun 17, 2026

CVE-2021-25667 is a high-severity vulnerability rated 8.8/10 on the CVSS scale. 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. EPSS estimates a 0.85% chance of exploitation in the next 30 days.

Description

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.

Metrics

CVSS 3.1

8.8/10

CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

EPSS Probability

0.85%

53.5th percentile

Probability of exploitation in the next 30 days. Learn more

Weakness Enumeration

Affected Software

Vendor	Product	Versions
Siemens	Ruggedcom Rm1224 Firmware	>= 4.3, < 6.4
Siemens	Scalance M-800 Firmware	>= 4.3, < 6.4
Siemens	Scalance S615 Firmware	>= 4.3, < 6.4
Siemens	Scalance X300wg Firmware	< 4.1
Siemens	Scalance Xm400 Firmware	< 6.2
Siemens	Scalance Xr500 Firmware	< 6.2
Siemens	Scalance Sc622-2c Firmware	<= 2.0
Siemens	Scalance Sc622-2c Firmware	>= 2.1, < 2.1.3
Siemens	Scalance Sc632-2c Firmware	<= 2.0
Siemens	Scalance Sc632-2c Firmware	>= 2.1, < 2.1.3
Siemens	Scalance Sc636-2c Firmware	<= 2.0
Siemens	Scalance Sc636-2c Firmware	>= 2.1, < 2.1.3
Siemens	Scalance Sc642-2c Firmware	<= 2.0
Siemens	Scalance Sc642-2c Firmware	>= 2.1, < 2.1.3
Siemens	Scalance Sc646-2c Firmware	<= 2.0
Siemens	Scalance Sc646-2c Firmware	>= 2.1, < 2.1.3
Siemens	Scalance Xb-200 Firmware	< 4.1
Siemens	Scalance Xc-200 Firmware	< 4.1
Siemens	Scalance Xf-200ba Firmware	< 4.1
Siemens	Scalance Xp-200 Firmware	< 4.1

References

https://cert-portal.siemens.com/productcert/pdf/ssa-979775.pdfPatch, Vendor Advisory
https://us-cert.cisa.gov/ics/advisories/icsa-21-068-03Patch, Third Party Advisory, US Government Resource
https://cert-portal.siemens.com/productcert/pdf/ssa-979775.pdfPatch, Vendor Advisory
https://us-cert.cisa.gov/ics/advisories/icsa-21-068-03Patch, Third Party Advisory, US Government Resource

Timeline

Published: Mar 15, 2021
Last Modified: Jun 17, 2026
Status: Modified

Frequently Asked Questions

What is CVE-2021-25667?

How severe is CVE-2021-25667?

CVE-2021-25667 has a CVSS score of 8.8/10 (HIGH severity). The EPSS model estimates a 0.85% probability of exploitation in the next 30 days.

How do I fix CVE-2021-25667?

Check the vendor references and advisories linked above for patched versions and mitigation guidance. You can also run a Strix scan to test if your systems are affected.

Are you affected by CVE-2021-25667?

Run a free Strix scan to check your systems for this vulnerability.

Scan your code now

Source: NVD / NIST