CVE-2021-25667

Severity: high (CVSS 8.8 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 1.0% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2021-03-15 · updated 2026-06-17
Weakness: CWE-121

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.

Affected products

Siemens Ruggedcom Rm1224 Firmware: from 4.3 before 6.4 — fixed in 6.4
Siemens Scalance M-800 Firmware: from 4.3 before 6.4 — fixed in 6.4
Siemens Scalance S615 Firmware: from 4.3 before 6.4 — fixed in 6.4
Siemens Scalance Sc622-2C Firmware: through 2.0; from 2.1 before 2.1.3 — fixed in 2.1.3
Siemens Scalance Sc632-2C Firmware: through 2.0; from 2.1 before 2.1.3 — fixed in 2.1.3
Siemens Scalance Sc636-2C Firmware: through 2.0; from 2.1 before 2.1.3 — fixed in 2.1.3
Siemens Scalance Sc642-2C Firmware: through 2.0; from 2.1 before 2.1.3 — fixed in 2.1.3
Siemens Scalance Sc646-2C Firmware: through 2.0; from 2.1 before 2.1.3 — fixed in 2.1.3
Siemens Scalance X300Wg Firmware: before 4.1 — fixed in 4.1
Siemens Scalance Xb-200 Firmware: before 4.1 — fixed in 4.1
Siemens Scalance Xc-200 Firmware: before 4.1 — fixed in 4.1
Siemens Scalance Xf-200Ba Firmware: before 4.1 — fixed in 4.1
Siemens Scalance Xm400 Firmware: before 6.2 — fixed in 6.2
Siemens Scalance Xp-200 Firmware: before 4.1 — fixed in 4.1
Siemens Scalance Xr500 Firmware: before 6.2 — fixed in 6.2

How to fix

Upgrade to a fixed version: Siemens Ruggedcom Rm1224 Firmware 6.4; Siemens Scalance M-800 Firmware 6.4; Siemens Scalance S615 Firmware 6.4; Siemens Scalance Sc622-2C Firmware 2.1.3; Siemens Scalance Sc632-2C Firmware 2.1.3; Siemens Scalance Sc636-2C Firmware 2.1.3; Siemens Scalance Sc642-2C Firmware 2.1.3; Siemens Scalance Sc646-2C Firmware 2.1.3; Siemens Scalance X300Wg Firmware 4.1; Siemens Scalance Xb-200 Firmware 4.1; Siemens Scalance Xc-200 Firmware 4.1; Siemens Scalance Xf-200Ba Firmware 4.1. Check the vendor advisory for mitigations.

References

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