CVE & CISA-KEV Catalog

CVE-2021-25667

HIGH
8.8
CVSS v3
NVD

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.

CWE-121Stack-based Buffer OverflowCWE-787Out-of-bounds Write

How to fix

Remediation Available
ruggedcom rm1224 firmwareNVD
Affected:>= 4.3, < 6.4Fixed in:6.4CVE-2021-25667derived from NVD
scalance m-800 firmwareNVD
Affected:>= 4.3, < 6.4Fixed in:6.4CVE-2021-25667derived from NVD
scalance s615 firmwareNVD
Affected:>= 4.3, < 6.4Fixed in:6.4CVE-2021-25667derived from NVD
scalance sc622-2c firmwareNVD
Affected:>= 2.1, < 2.1.3Fixed in:2.1.3CVE-2021-25667derived from NVD
scalance sc632-2c firmwareNVD
Affected:>= 2.1, < 2.1.3Fixed in:2.1.3CVE-2021-25667derived from NVD
scalance sc636-2c firmwareNVD
Affected:>= 2.1, < 2.1.3Fixed in:2.1.3CVE-2021-25667derived from NVD
scalance sc642-2c firmwareNVD
Affected:>= 2.1, < 2.1.3Fixed in:2.1.3CVE-2021-25667derived from NVD
scalance sc646-2c firmwareNVD
Affected:>= 2.1, < 2.1.3Fixed in:2.1.3CVE-2021-25667derived from NVD
scalance x300wg firmwareNVD
Affected:< 4.1Fixed in:4.1CVE-2021-25667derived from NVD
scalance xb-200 firmwareNVD
Affected:< 4.1Fixed in:4.1CVE-2021-25667derived from NVD
scalance xc-200 firmwareNVD
Affected:< 4.1Fixed in:4.1CVE-2021-25667derived from NVD
scalance xf-200ba firmwareNVD
Affected:< 4.1Fixed in:4.1CVE-2021-25667derived from NVD
scalance xm400 firmwareNVD
Affected:< 6.2Fixed in:6.2CVE-2021-25667derived from NVD
scalance xp-200 firmwareNVD
Affected:< 4.1Fixed in:4.1CVE-2021-25667derived from NVD
scalance xr500 firmwareNVD
Affected:< 6.2Fixed in:6.2CVE-2021-25667derived from NVD

Remediation is compiled from vendor and distribution security advisories. Always confirm against the linked source for your exact version and platform.

CVSS v3 Vector

Exploitability

Attack VectorAdjacent
Attack ComplexityLow
Privileges RequiredNone
User InteractionNone
ScopeUnchanged

Impact

ConfidentialityHigh
IntegrityHigh
AvailabilityHigh

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

Exploit Intelligence

0.85%probability of exploitation in 30 days
54thpercentile

Moderate risk: more likely to be exploited than 54% of all known CVEs.

References

Related Vulnerabilities

Other CWE-121 (Stack-based Buffer Overflow) vulnerabilities, ordered by exploit likelihood. View all

CVESeverityCVSSEPSSExploitedFix
CVE-2025-22457Critical9.0100%KEV + RansomFix
CVE-2025-0282Critical9.0100%KEV + Ransom-
CVE-2021-20038Critical9.8100%KEV + Ransom-
CVE-2009-0927High8.897%KEVFix
CVE-2020-10924High8.887%--
CVE-2022-20705Critical10.080%--
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This product uses NVD data but is not endorsed or certified by the NVD. EPSS scores courtesy of FIRST.org (https://www.first.org/epss). Source: CISA KEV Catalog. Data as of 2026-06-02.