What is CVE-2021-26639?

CVE-2021-26639 is a high-severity vulnerability in Linux Kernel, classified under Improper Input Validation. CVSS score: 8.1/10. Published 2022-08-17.

How severe is CVE-2021-26639?

High severity. CVSS v3 base score is 8.1 out of 10.

Improper input validation in Linux Kernel

CVE-2021-26639

This vulnerability is caused by the lack of validation of input values for specific functions if WISA Smart Wing CMS. Remote attackers can use this vulnerability to leak all files in the server without logging in system.

Vulnerability class: Drupalgeddon 2 (CVE-2018-7600)

Published 2022-08-17 · last modified 2026-06-17.

CVSS v3 metric

CVSS v3 base score 8.1 (High). Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:N.

EPSS exploit prediction

EPSS: 0.005 (37.0th percentile), scored 2026-10-01.

Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 37th percentile — 37.0% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS over last 30 days · oldest: 0.005 · newest: 0.005 · change: 0.000

Affected products

Linux Kernel
Wisa Smart Wing Cms
Wisa Corp. Smart Wing Cms — versions unspecified

Weakness classification (CWE)

References

www.krcert.or.kr/krcert/secNoticeView.do (Third Party Advisory)

Frequently asked questions

What is CVE-2021-26639?: CVE-2021-26639 is a high-severity vulnerability in Linux Kernel, classified under Improper Input Validation. CVSS score: 8.1/10. Published 2022-08-17.
How severe is CVE-2021-26639?: High severity. CVSS v3 base score is 8.1 out of 10.