What is the CVSS score of CVE-2021-20853?

CVE-2021-20853 has a CVSS 3.1 base score of 6.8 (Medium). CVSS vector: CVSS:3.1/AV:A/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:H. EPSS exploitation probability: 0.4%.

Wrh 733Gbk Firmware CVE-2021-20853

MEDIUM

OS Command Injection (CWE-78)

2021-12-01 vultures@jpcert.or.jp

Command Injection Wrh 733Gbk Firmware Wrh 733Gwh Firmware

6.8

CVSS 3.1 · NVD

Severity by source

NVD PRIMARY

6.8 MEDIUM

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

Primary rating from NVD · only source for this CVE.

CVSS VectorNVD

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

Attack Vector

Adjacent

Attack Complexity

Low

Privileges Required

High

User Interaction

None

Scope

Unchanged

Confidentiality

High

Integrity

High

Availability

High

Lifecycle Timeline

CVE Published

Dec 01, 2021 - 03:15 nvd

MEDIUM 6.8

DescriptionNVD

ELECOM LAN routers (WRH-733GBK firmware v1.02.9 and prior and WRH-733GWH firmware v1.02.9 and prior) allows a network-adjacent attacker with an administrator privilege to execute arbitrary OS commands via unspecified vectors.

AnalysisAI

Technical ContextAI

This vulnerability is classified as OS Command Injection (CWE-78), which allows attackers to execute arbitrary operating system commands on the host. ELECOM LAN routers (WRH-733GBK firmware v1.02.9 and prior and WRH-733GWH firmware v1.02.9 and prior) allows a network-adjacent attacker with an administrator privilege to execute arbitrary OS commands via unspecified vectors. Affected products include: Elecom Wrh-733Gbk Firmware, Elecom Wrh-733Gwh Firmware.

RemediationAI

No vendor patch is available at time of analysis. Monitor vendor advisories for updates. Avoid passing user input to shell commands. Use language-specific APIs instead of shell execution. Apply strict input validation with allowlists.