CVE-2021-20852

Name: CVE-2021-20852
Creator: NVD / NIST
Published: 2021-12-01T03:15:06.713+00:00
License: https://creativecommons.org/publicdomain/zero/1.0/

MEDIUMCVSS 6.8/10EPSS 0.45%

Last modified Jun 17, 2026

CVE-2021-20852 is a medium-severity vulnerability rated 6.8/10 on the CVSS scale. Buffer overflow vulnerability in 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 an arbitrary OS command via unspecified vectors.. EPSS estimates a 0.45% chance of exploitation in the next 30 days.

Description

Buffer overflow vulnerability in 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 an arbitrary OS command via unspecified vectors.

Metrics

CVSS 3.1

6.8/10

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

EPSS Probability

0.45%

36.1th percentile

Probability of exploitation in the next 30 days. Learn more

Weakness Enumeration

CWE-120

Affected Software

Vendor	Product	Versions
Elecom	Wrh-733gbk Firmware	<= 1.02.9
Elecom	Wrh-733gwh Firmware	<= 1.02.9

References

https://jvn.jp/en/jp/JVN88993473/index.htmlThird Party Advisory
https://www.elecom.co.jp/news/security/20211130-01/Vendor Advisory
https://jvn.jp/en/jp/JVN88993473/index.htmlThird Party Advisory
https://www.elecom.co.jp/news/security/20211130-01/Vendor Advisory

Timeline

Published: Dec 1, 2021
Last Modified: Jun 17, 2026
Status: Modified

Frequently Asked Questions

What is CVE-2021-20852?

How severe is CVE-2021-20852?

CVE-2021-20852 has a CVSS score of 6.8/10 (MEDIUM severity). The EPSS model estimates a 0.45% probability of exploitation in the next 30 days.

How do I fix CVE-2021-20852?

Check the vendor references and advisories linked above for patched versions and mitigation guidance. You can also run a Strix scan to test if your systems are affected.

Are you affected by CVE-2021-20852?

Run a free Strix scan to check your systems for this vulnerability.

Scan your code now

Source: NVD / NIST