Cyber Resilience

CVE-2021-20863

High

Published: 01 December 2021

Published
01 December 2021
Modified
21 November 2024
KEV Added
—
Patch
—
CVSS Score v3.1 8.0 CVSS:3.1/AV:A/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
EPSS Score 0.0124 79.7th percentile
Risk Priority 17 60% EPSS · 20% KEV · 20% CVSS

Summary

CVE-2021-20863 is a high-severity OS Command Injection (CWE-78) vulnerability in Elecom Wrc-1167Gst2 Firmware. Its CVSS base score is 8.0 (High).

Operationally, ranked in the top 20.3% of CVEs by exploit likelihood; it is not currently listed in the CISA KEV catalog.

EU & UK References

Vulnerability details

OS command injection vulnerability in ELECOM routers (WRC-1167GST2 firmware v1.25 and prior, WRC-1167GST2A firmware v1.25 and prior, WRC-1167GST2H firmware v1.25 and prior, WRC-2533GS2-B firmware v1.52 and prior, WRC-2533GS2-W firmware v1.52 and prior, WRC-1750GS firmware v1.03 and prior, WRC-1750GSV firmware v2.11…

more

and prior, WRC-1900GST firmware v1.03 and prior, WRC-2533GST firmware v1.03 and prior, WRC-2533GSTA firmware v1.03 and prior, WRC-2533GST2 firmware v1.25 and prior, WRC-2533GST2SP firmware v1.25 and prior, WRC-2533GST2-G firmware v1.25 and prior, and EDWRC-2533GST2 firmware v1.25 and prior) allows a network-adjacent authenticated attackers to execute an arbitrary OS command with the root privilege 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-1167gst2 firmware
≤ 1.25
elecom
wrc-1167gst2a firmware
≤ 1.25
elecom
wrc-1167gst2h firmware
≤ 1.25
elecom
wrc-2533gs2-b firmware
≤ 1.52
elecom
wrc-2533gs2-w firmware
≤ 1.52
elecom
wrc-1750gs firmware
≤ 1.03
elecom
wrc-1750gsv firmware
≤ 2.11
elecom
wrc-1900gst firmware
≤ 1.03
elecom
wrc-2533gst firmware
≤ 1.03
elecom
wrc-2533gst2 firmware
≤ 1.25
+4 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