Cyber Resilience

CVE-2021-20739

High

Published: 07 July 2021

Published
07 July 2021
Modified
21 November 2024
KEV Added
—
Patch
—
CVSS Score v3.1 8.8 CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
EPSS Score 0.0033 56.5th percentile
Risk Priority 18 60% EPSS · 20% KEV · 20% CVSS

Summary

CVE-2021-20739 is a high-severity OS Command Injection (CWE-78) vulnerability in Elecom Wrc-300Febk Firmware. Its CVSS base score is 8.8 (High).

Operationally, ranked in the top 43.5% of CVEs by exploit likelihood; it is not currently listed in the CISA KEV catalog.

EU & UK References

Vulnerability details

WRC-300FEBK, WRC-F300NF, WRC-733FEBK, WRH-300RD, WRH-300BK, WRH-300SV, WRH-300WH, WRH-H300WH, WRH-H300BK, WRH-300BK-S, and WRH-300WH-S all versions allows an unauthenticated network-adjacent attacker to execute an arbitrary OS command via unspecified vectors.

CWE(s)
CWE-78

Related Threats

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

Affected Assets

elecom
wrc-300febk firmware
all versions
elecom
wrc-f300nf firmware
all versions
elecom
wrc-733febk firmware
all versions
elecom
wrh-300rd firmware
all versions
elecom
wrh-300bk firmware
all versions
elecom
wrh-300sv firmware
all versions
elecom
wrh-300wh firmware
all versions
elecom
wrh-h300wh firmware
all versions
elecom
wrh-h300bk firmware
all versions
elecom
wrh-300bk-s firmware
all versions
+1 more product configuration(s) — see NVD for full list

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.

SC-27 Platform-independent Applications
addresses: CWE-78

Platform-independent apps typically execute inside a managed runtime or sandbox that restricts direct OS command execution, reducing the ability to exploit OS command injection.

SI-10 Information Input Validation
addresses: CWE-78

Validates inputs to block special elements that would alter OS command execution.

References