CVE-2020-8821
An Improper Data Validation Vulnerability exists in Webmin 1.941 and earlier affecting the...
An Improper Data Validation Vulnerability exists in Webmin 1.941 and earlier affecting the Command Shell Endpoint. A user may enter HTML code into the Command field and submit it. Then, after visiting the Action Logs Menu and displaying logs, the HTML code will be rendered (however, JavaScript is not executed). Changes are kept across users.
Attack profile
How easy it is to exploit
- Attack vector
- Network
- Complexity
- Low
- Privileges needed
- Low
- User interaction
- Required
What an attacker can affect
- Confidentiality
- Low
- Integrity
- Low
- Availability
- None
Exploit likelihood
What each source reports
NVD Score used
5.4
An Improper Data Validation Vulnerability exists in Webmin 1.941 and earlier affecting the Command Shell Endpoint. A user may enter HTML code into the Command field and submit it. Then, after visiting the Action Logs Menu and displaying logs, the HTML code will be rendered (however, JavaScript is not executed). Changes are kept across users.
- Record
CVE-2020-8821- CVSS 3.1
- 5.4 Medium
CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:L/I:L/A:N - CVSS 2.0
- 3.5 Low
AV:N/AC:M/Au:S/C:N/I:P/A:N - Weakness
- CWE-79
- Updated
- 2026-11-02
CVE List No score
An Improper Data Validation Vulnerability exists in Webmin 1.941 and earlier affecting the Command Shell Endpoint. A user may enter HTML code into the Command field and submit it. Then, after visiting the Action Logs Menu and displaying logs, the HTML code will be rendered (however, JavaScript is not executed). Changes are kept across users.
- Record
CVE-2020-8821- Updated
- 2026-11-02
EUVDEUVD-2020-29667 No score
An Improper Data Validation Vulnerability exists in Webmin 1.941 and earlier affecting the Command Shell Endpoint. A user may enter HTML code into the Command field and submit it. Then, after visiting the Action Logs Menu and displaying logs, the HTML code will be rendered (however, JavaScript is not executed). Changes are kept across users.
- Record
EUVD-2020-29667- Updated
- 2026-11-03
GitHub AdvisoriesGHSA-2gmj-rvcm-f6j2 No score
An Improper Data Validation Vulnerability exists in Webmin 1.941 and earlier affecting the...
An Improper Data Validation Vulnerability exists in Webmin 1.941 and earlier affecting the Command Shell Endpoint. A user may enter HTML code into the Command field and submit it. Then, after visiting the Action Logs Menu and displaying logs, the HTML code will be rendered (however, JavaScript is not executed). Changes are kept across users.
- Record
GHSA-2gmj-rvcm-f6j2- Weakness
- CWE-74
- Updated
- 2026-11-02
OSV
5.4
An Improper Data Validation Vulnerability exists in Webmin 1.941 and earlier affecting the Command Shell Endpoint. A user may enter HTML code into the Command field and submit it. Then, after visiting the Action Logs Menu and displaying logs, the HTML code will be rendered (however, JavaScript is not executed). Changes are kept across users.
- Record
CVE-2020-8821- CVSS 3.1
- 5.4 Medium
CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:L/I:L/A:N - Updated
- 2026-11-02
OSVMGASA-2020-0400 No score
Updated webmin package fixes security vulnerabilities
An XSS Vulnerability exists in Webmin 1.941 and earlier affecting the Cluster Shell Commands Endpoint. A user may enter any XSS Payload into the Command field and execute it. Then, after revisiting the Cluster Shell Commands Menu, the XSS Payload will be rendered and executed. (CVE-2020-8820)
An Improper Data Validation Vulnerability exists in Webmin 1.941 and earlier affecting the Command Shell Endpoint. A user may enter HTML code into the Command field and submit it. Then, after visiting the Action Logs Menu and displaying logs, the HTML code will be rendered (however, JavaScript is not executed). Changes are kept across users. (CVE-2020-8821)
XSS exists in Webmin 1.941 and earlier affecting the Save function of the Read User Email Module / mailboxes Endpoint when attempting to save HTML emails. This module parses any output without sanitizing SCRIPT elements, as opposed to the View function, which sanitizes the input correctly. A malicious user can send any JavaScript payload into the message body and execute it if the user decides to save that email. (CVE-2020-12670)
- Record
MGASA-2020-0400- Updated
- 2026-11-02
Affected products
Affected packages
| Package | Affected | Fixed |
|---|---|---|
webminMageia:7 From an advisory covering 3 CVEs |
before 1.960-1.mga7 | 1.960-1.mga7 |
History
| Recorded | Changed | Sources |
|---|---|---|
| affected, facts | ||
| aliases | EUVD | |
| first indexed | CVE List, GitHub Advisories, NVD, OSV |
Dates are when Every CVE recorded each change. Upstream dates may differ.
In short
CVE-2020-8821 is a medium vulnerability (CVSS 5.4) in Webmin, published October 12, 2020. No source lists public exploit code. EPSS puts the chance of exploitation in the next 30 days at 79.1%, the 99th percentile. No source names a fixed version.