Cyber Resilience

CVE-2021-42020

High

Published: 08 March 2022

Published
08 March 2022
Modified
12 August 2025
KEV Added
—
Patch
—
CVSS Score v3.1 7.5 CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
EPSS Score 0.0034 57.0th percentile
Risk Priority 15 60% EPSS · 20% KEV · 20% CVSS

Summary

CVE-2021-42020 is a high-severity Improper Check for Unusual or Exceptional Conditions (CWE-754) vulnerability in Siemens Ruggedcom Ros. Its CVSS base score is 7.5 (High).

Operationally, ranked in the top 43.0% of CVEs by exploit likelihood; it is not currently listed in the CISA KEV catalog.

EU & UK References

Vulnerability details

A vulnerability has been identified in RUGGEDCOM i800, RUGGEDCOM i800NC, RUGGEDCOM i801, RUGGEDCOM i801NC, RUGGEDCOM i802, RUGGEDCOM i802NC, RUGGEDCOM i803, RUGGEDCOM i803NC, RUGGEDCOM M2100, RUGGEDCOM M2100NC, RUGGEDCOM M2200, RUGGEDCOM M2200NC, RUGGEDCOM M969, RUGGEDCOM M969NC, RUGGEDCOM RMC30, RUGGEDCOM RMC30NC, RUGGEDCOM RMC8388…

more

V4.X, RUGGEDCOM RMC8388 V5.X, RUGGEDCOM RMC8388NC V4.X, RUGGEDCOM RMC8388NC V5.X, RUGGEDCOM RP110, RUGGEDCOM RP110NC, RUGGEDCOM RS1600, RUGGEDCOM RS1600F, RUGGEDCOM RS1600FNC, RUGGEDCOM RS1600NC, RUGGEDCOM RS1600T, RUGGEDCOM RS1600TNC, RUGGEDCOM RS400, RUGGEDCOM RS400NC, RUGGEDCOM RS401, RUGGEDCOM RS401NC, RUGGEDCOM RS416, RUGGEDCOM RS416NC, RUGGEDCOM RS416NCv2 V4.X, RUGGEDCOM RS416NCv2 V5.X, RUGGEDCOM RS416P, RUGGEDCOM RS416PNC, RUGGEDCOM RS416PNCv2 V4.X, RUGGEDCOM RS416PNCv2 V5.X, RUGGEDCOM RS416Pv2 V4.X, RUGGEDCOM RS416Pv2 V5.X, RUGGEDCOM RS416v2 V4.X, RUGGEDCOM RS416v2 V5.X, RUGGEDCOM RS8000, RUGGEDCOM RS8000A, RUGGEDCOM RS8000ANC, RUGGEDCOM RS8000H, RUGGEDCOM RS8000HNC, RUGGEDCOM RS8000NC, RUGGEDCOM RS8000T, RUGGEDCOM RS8000TNC, RUGGEDCOM RS900, RUGGEDCOM RS900 (32M) V4.X, RUGGEDCOM RS900 (32M) V5.X, RUGGEDCOM RS900G, RUGGEDCOM RS900G (32M) V4.X, RUGGEDCOM RS900G (32M) V5.X, RUGGEDCOM RS900GNC, RUGGEDCOM RS900GNC(32M) V4.X, RUGGEDCOM RS900GNC(32M) V5.X, RUGGEDCOM RS900GP, RUGGEDCOM RS900GPNC, RUGGEDCOM RS900L, RUGGEDCOM RS900LNC, RUGGEDCOM RS900M-GETS-C01, RUGGEDCOM RS900M-GETS-XX, RUGGEDCOM RS900M-STND-C01, RUGGEDCOM RS900M-STND-XX, RUGGEDCOM RS900MNC-GETS-C01, RUGGEDCOM RS900MNC-GETS-XX, RUGGEDCOM RS900MNC-STND-XX, RUGGEDCOM RS900MNC-STND-XX-C01, RUGGEDCOM RS900NC, RUGGEDCOM RS900NC(32M) V4.X, RUGGEDCOM RS900NC(32M) V5.X, RUGGEDCOM RS900W, RUGGEDCOM RS910, RUGGEDCOM RS910L, RUGGEDCOM RS910LNC, RUGGEDCOM RS910NC, RUGGEDCOM RS910W, RUGGEDCOM RS920L, RUGGEDCOM RS920LNC, RUGGEDCOM RS920W, RUGGEDCOM RS930L, RUGGEDCOM RS930LNC, RUGGEDCOM RS930W, RUGGEDCOM RS940G, RUGGEDCOM RS940GNC, RUGGEDCOM RS969, RUGGEDCOM RS969NC, RUGGEDCOM RSG2100, RUGGEDCOM RSG2100 (32M) V4.X, RUGGEDCOM RSG2100 (32M) V5.X, RUGGEDCOM RSG2100NC, RUGGEDCOM RSG2100NC(32M) V4.X, RUGGEDCOM RSG2100NC(32M) V5.X, RUGGEDCOM RSG2100P, RUGGEDCOM RSG2100P (32M) V4.X, RUGGEDCOM RSG2100P (32M) V5.X, RUGGEDCOM RSG2100PNC, RUGGEDCOM RSG2100PNC (32M) V4.X, RUGGEDCOM RSG2100PNC (32M) V5.X, RUGGEDCOM RSG2200, RUGGEDCOM RSG2200NC, RUGGEDCOM RSG2288 V4.X, RUGGEDCOM RSG2288 V5.X, RUGGEDCOM RSG2288NC V4.X, RUGGEDCOM RSG2288NC V5.X, RUGGEDCOM RSG2300 V4.X, RUGGEDCOM RSG2300 V5.X, RUGGEDCOM RSG2300NC V4.X, RUGGEDCOM RSG2300NC V5.X, RUGGEDCOM RSG2300P V4.X, RUGGEDCOM RSG2300P V5.X, RUGGEDCOM RSG2300PNC V4.X, RUGGEDCOM RSG2300PNC V5.X, RUGGEDCOM RSG2488 V4.X, RUGGEDCOM RSG2488 V5.X, RUGGEDCOM RSG2488NC V4.X, RUGGEDCOM RSG2488NC V5.X, RUGGEDCOM RSG907R, RUGGEDCOM RSG908C, RUGGEDCOM RSG909R, RUGGEDCOM RSG910C, RUGGEDCOM RSG920P V4.X, RUGGEDCOM RSG920P V5.X, RUGGEDCOM RSG920PNC V4.X, RUGGEDCOM RSG920PNC V5.X, RUGGEDCOM RSL910, RUGGEDCOM RSL910NC, RUGGEDCOM RST2228, RUGGEDCOM RST2228P, RUGGEDCOM RST916C, RUGGEDCOM RST916P. The third-party component, in its TFTP functionality fails to check for null terminations in file names. If an attacker were to exploit this, it could result in data corruption, and possibly a hard-fault of the application.

CWE(s)
CWE-754

Related Threats

No named actor attribution yet. ATT&CK technique mapping in progress for this CVE.

Affected Assets

siemens
ruggedcom ros
all versions · ≤ 5.6.0

Mitigating Controls

Likely Mitigating Controls AI

Per-CVE control mapping for this CVE has not run yet; the list below is derived from the weakness types (CWEs) cited in the NVD entry.

AU-5 Response to Audit Logging Process Failures
addresses: CWE-754

Requires detection and response to audit logging failures as an unusual or exceptional condition.

CP-12 Safe Mode
addresses: CWE-754

Implements detection of unusual or exceptional conditions followed by safe mode entry, reducing the window for exploitation of unchecked conditions.

CP-3 Contingency Training
addresses: CWE-754

Training ensures users perform required checks for unusual or exceptional conditions as part of contingency roles, limiting attacker leverage from skipped validations.

IR-3 Incident Response Testing
addresses: CWE-754

IR testing directly validates checks for unusual or exceptional conditions that could indicate security incidents.

PM-31 Continuous Monitoring Strategy
addresses: CWE-754

Requires ongoing monitoring of organization-defined metrics and analysis, enabling checks for unusual or exceptional conditions.

SA-11 Developer Testing and Evaluation
addresses: CWE-754

Security testing routinely checks for unusual or exceptional inputs/conditions, identifying missing validation steps that flaw remediation then resolves.

SC-24 Fail in Known State
addresses: CWE-754

Requires detection of unusual conditions followed by a controlled transition to the defined failure state.

SI-13 Predictable Failure Prevention
addresses: CWE-754

MTTF determination forces explicit checks for conditions that precede predictable component failure.

References